Resident

Our Residents

First Year Residents 

Sergio Aleman MDSergio Aleman, MD

Hello there! I was born and raised in San Antonio as the oldest of four siblings. I enjoy watching sports (big Spurs and Barcelona fan) and spending time with my wife and family. I went to undergrad at the University of Texas at Austin where I studied sociology and biology. Some of my favorite experiences during my time at UT was to study abroad in England and to perform with the UT Mariachi. Eventually, I was fortunate to attend medical school in my hometown at UT Health San Antonio. I have always been interested in family medicine throughout my education due to my own personal experiences that led me to want to be a family doctor myself. I am glad to be part of a supportive program and to be able to complete my training so close to home.

Cara Anderson MDCara Anderson, MD

Hey y’all! I am from Carrollton, Texas. I started undergrad at Pepperdine University and then transferred to the University of Texas at Austin (Hook 'em, Horns!) where I graduated with my bachelor’s degree. I went to UTMB in Galveston, Texas for medical school and am super excited to be back in the Texas Hill Country in San Antonio for residency! Things I love include all types of music, trying out different coffee shops and breweries, and my sweet pup, Ladybird.

I chose CHRISTUS first and foremost because of the family-feel of the program. The residents, faculty, and coordinators are so welcoming and clearly demonstrate how much they love working together and hanging out outside of work. I also chose CHRISTUS for the complexity of training we get here in a community setting between managing ICU patients, delivering babies, working at the children's hospital, and more. There are endless opportunities for learning here! I'm honored to be working alongside amazingly personable and intelligent residents and attendings.

Oscar Gonzalez MDOscar Gonzalez, MD

I am from the Mid Cities area near Fort Worth, TX. I have graduate research training in molecular radiation biology and used to teach basic sciences as an adjunct instructor in community colleges and medical assisting programs. I decided to change careers and pursue a career in medicine to continue my learning, apply my knowledge of basic science, and use my skills in teaching and communication to help my community.

I chose family medicine because it was the field of medicine most integrated in my life. From my geriatric parents, to my personal problems with my creaky knees, to my pediatric grandchildren, family medicine is connected to every aspect of my life. I chose CHRISTUS Santa Rosa because I found it to be the most welcoming and supportive residency program I could find.

Sabina N Lalani DOSabina Lalani, DO

Hi y’all, thank you for taking a minute to get to know me! I grew up in Sugar Land, TX and my family is from Burma, Bangladesh and Pakistan. I went to undergrad at Trinity University in San Antonio and studied abroad in London. I took a gap year before medical school and completed a Master of Arts in Medical Sciences at Loyola University Chicago. Right before I started at UIW School of Osteopathic Medicine in San Antonio, I did an internship in Hydrabad, India which further solidified my passion for working in underserved communities. I was drawn to Family Medicine because I loved all my core rotations and enjoy diversity in my day. I have a passion for women’s health, enjoy seeing pediatric patients, and really like building connections with my patients in the clinic. I ranked CHRISTUS Santa Rosa as my top choice because during my 4th year audition rotation I was able to see the amazing learning opportunities the residents at CHRISTUS had access to daily. I wanted to go to an unopposed program that provided me a solid foundation to grow as a physician and one that had a supportive family environment.

Finally, I wanted to share a little bit about myself. If it was not apparent from above, I love to travel and explore cultures and foods from around the globe! I enjoy playing basketball and volleyball, as well as hosting game nights for my family and friends. My fiancé and I recently got a corgi so lately we have enjoyed spending time outdoors and teaching her new tricks.

Eloy Martinez Jr. DOEloy Martinez, DO

I was born and raised in the small, South Texas border town of Zapata. I completed my Bachelors of Science in Biology at Texas A&M International University in 2017. I then moved to San Antonio to pursue both my Masters in Biomedical Sciences and Doctor of Osteopathic Medicine at the University of the Incarnate Word School of Osteopathic Medicine.

I chose a career in medicine after recognizing, both personally and through loved ones, the healthcare disparities that impact rural minority populations. I then pursued family medicine specifically given my passion for preventative care and appreciation for the versatility that this specialty provides professionally and clinically. I am currently considering pursuing a sports medicine fellowship to provide care in the future to my home community and local public school athletes. I chose CHRISTUS for its supportive and collaborative culture, the passion for teaching displayed by its residency faculty, and the flexibility of the program to tailor each residents training to complement their future career aspirations.

Bethany Pierce MDBethany Pierce, MD

I was born in San Antonio but raised in a small town called Monett in Missouri. I moved back to Texas as a teenager and went to high school in College Station, college at TCU in Fort Worth, and medical school at UT Health in San Antonio. I chose Family Medicine because I value connecting with and caring for patients, and this field provides continuity of care, a broad scope of practice, and a wide variety of career options to make that possible. I chose CHRISTUS because of the people, the community-based environment, and the opportunity to learn a diverse set of skills as a family medicine doctor in numerous healthcare settings.

Sara Stubbs-Walden MDSara Stubbs-Walden, MD

Hi there! I was born and raised in the Rio Grande Valley, a wonderful place in the southernmost tip of Texas. I completed my undergraduate studies at the University of Texas Rio Grande Valley where I majored in Biology. I was part of an early medical school acceptance program that granted me conditional acceptance to the University of Texas Medical Branch when I was 18! Thankfully, I was able to complete the program and I successfully matriculated to UTMB following my college graduation. I moved to Galveston and lived the island life for medical school. I made life-long friends during my time there and I was fortunate enough that they all moved to San Antonio for residency! I also met my husband (and fellow intern), David at the end of our first year of school. We got married right in the middle of interview season and amidst a COVID surge, but it was truly a magical day. I chose a career in Family Medicine because I believe that family physicians can have such a positive influence in the lives of patients. I genuinely enjoy making connections with people. Talking to and learning about the people I care for is incredibly important to me. I am also passionate about educating patients on their chronic conditions and advancing their health literacy. I chose CHRISTUS for my residency for several reasons. They offered me all the training opportunities I wanted as a full scope, unopposed, community program. They also made me and my husband feel so welcomed and cared for during the interview process. I truly felt that I would fit in perfectly at this program and this community. I am so excited to learn and grow here at CHRISTUS, and I can already tell that I am surrounded by some pretty amazing people!

Jordan Ta DOJordan Ta, DO

Hello friends! It’s a pleasure to meet you! My name is Jordan and I was born and raised in Fort Worth, Texas. I completed my undergraduate education at Texas Tech University in Lubbock, Texas. I attended medical school at UIW School of Osteopathic Medicine here in San Antonio. I am blessed with a wonderful wife and a sweet baby girl. Fun facts: I love music and playing guitar, I have a passion for cooking, and my wife and I are the biggest foodies you will meet! Since starting our journey in San Antonio, we have enjoyed trying and discovering the diverse culture and cuisines this city has to offer!

I chose family medicine because I wanted to be well-equipped to treat patients of all ages and of all different conditions. In addition, I found that primary care physicians have the unique opportunity to develop long-term relationships with their patients. I love being a resident at CHRISTUS Santa Rosa because of the unopposed full-spectrum training it offers and the family-like environment of all the residents and staff. I am confident that my training here will help me to succeed in pursuing any career in family medicine.

David Walden MDDavid Walden, MD

I was born and raised in a small town, 30 minutes south of Dallas. I went to Oklahoma Christian University, where I studied biology and played the bassoon. I followed my brother in going to the University of Texas Medical Branch for medical school, where I fostered interests in mindfulness and evidence-based medicine; starting my own journal club newsletter. I enjoy listening to podcasts, playing games, watching movies, and spending time with my wife and 2 cats, Loki and Kiki.

Taylor Works MDTaylor Works, MD

Hello! I was born and raised in the Westlake area of Austin, where I was fortunate to get an early start with my love of the sciences. It was during those early days that I also met my wife, Lorraine, whom I’ve known since the 6th grade and has been my greatest supporter along this exciting journey. My early inspiration to pursue a career in medicine came from the legacy of my grandfather, who was a beloved physician that left a lasting impact on the people of Brownsville, Texas, where he lived and practiced for many years. After high school, I moved to College Station to attend Texas A&M University, where I received my Bachelor of Science in biology and got more exposure to the medical field through opportunities like cancer research, clinical volunteering, and working as a phlebotomist. It was these experiences that solidified my passion for medicine and I went on to join the Long School of Medicine class of 2022 at the UT Health Science Center here in San Antonio. I found my love of Family Medicine during my 3rd year rotations when I saw the immense need for high quality primary care and the endless practice and career opportunities that come with it. In my free time, I enjoy cooking, outdoor activities like fishing and hiking, and finding new and exciting activities and restaurants around San Antonio with my wife.

I am so grateful for the opportunity to join the class of 2025 at the CHRISTUS Santa Rosa Family Medicine Residency, which was my first choice. CHRISTUS is the perfect program for me because I want to be challenged with vigorous full-scope, unopposed training that will truly prepare me to practice in any environment. From my first interaction with the program, I could feel the supportive family-oriented atmosphere that many residencies claim to have but only few truly possess. I’m excited to learn from our faculty, who are heavily invested in our professional development, and lucky to have the opportunity to continue caring for the patient population of San Antonio that I have come to know and love.

Second Year Residents 

A headshot of Sandra GeorgeSandra George DO, PA-C, RD, LD

I grew up all over the US but consider San Antonio home. I attended UT Austin for undergrad, then went to Albany Medical College for PA school and lastly went to Lake Erie College of Osteopathic Medicine for medical school.

I look forward to a servant mentality encompassed by the Christus network in the practice of medicine and in treating patients.

I don’t have any one single hobby (wish I did!) but enjoy hanging out with family, friends, traveling (been to more about 20 countries and counting!), eating, working out and baking. These are some of my favorite things. But always open to trying more things out like skydiving and what not!


A headshot of  Timothy HoverTimothy Hover, DO

Hey y’all—yes, I’m a true Texan—born and raised here in San Antonio. I was a non-traditional medical student, with a near three-year gap between my undergrad completion at the University of the Incarnate Word (UIW) and starting medical school as a member of UIW’s inaugural class. During my gap years, I began working with H-E-B pharmacy, which continued into the early part of my second year of medical school.

I am an avid NBA and NFL fan. My favorite teams are the San Antonio Spurs and the Minnesota Vikings, respectively. I also dabble in a bit of Fantasy Football. I have two rescue dogs named Kiwi and Brownie. Kiwi is a Golden Retriever, and Brownie is part retriever and part sneaky neighborhood dog.

I ranked Christus Santa Rosa as my top choice for three reasons. First, Christus is an excellent learning and teaching hospital, and being an unopposed program is a bonus. Second, the program has a solid supportive family feel, which I noticed during my interactions with residents at local TAFP chapter meetings. Lastly, I have an emotional connection because my grandmother worked for the original Santa Rosa Hospital as a housekeeper for 19 years before retiring. Although my grandmother is no longer with me physically, being a part of the Christus family only strengthens our shared bond.

My near-term goals include learning and applying as much medical knowledge as possible while being a supportive and helpful teammate. Ultimately, I want to remain in San Antonio because there is such a tremendous opportunity to help care for, educate, and empower the growing population base into taking a more active role in their personal health.


A headshot of Tawanda Stephen KamuchekaStephen Kamucheka, MD

My interest in medicine dates to my childhood in Harare, Zimbabwe. My mother was a long-time nurse and midwife, and I had the opportunity to watch her work with her patients every time that I visited her at her workplace at a tender age. She also kept numerous medicine textbooks in our modest bookshelf at home and I thoroughly enjoyed flipping through the pages and reading about the various medical conditions I came across. As I progressed through school, it became clear to me that science was my passion and that I wanted to pursue a career in healthcare. After moving to the US, I attended the University of Texas at San Antonio where I earned a bachelor’s degree in Biology followed by enrollment at the University of Texas Medical Branch at Galveston where I completed my medical degree.

At CHRISTUS Santa Rosa, I look forward to learning from faculty that are dedicated to the professional growth, development, and success of their residents. The diverse patient population I will care for will also offer unlimited learning opportunities. I also look forward to some of the long-term patient-physician relationships that I will form as I work with a diverse patient population.

Outside of the clinic/hospital, I enjoy playing or watching tennis, soccer, or going fishing or on a bike ride.


A headshot of Krystal KwongKrystal Kwong, DO

I was born and raised in none other than Sugar Land, Texas. I grew up as the middle child with two other sisters. I attended Houston Baptist University (Dogs Up!) and chased my love for science by graduating with a degree in biochemistry and molecular biology in 2016. One year later, I was delighted to receive an acceptance letter to the brand new University of the Incarnate Word School of Osteopathic Medicine. With the love, support, and encouragement from family and loved ones, I was able to finally earn my degree in osteopathic medicine in May 2021.

I cannot wait to build meaningful relationships with my patients and lifelong friendships with my co-interns and co-residents! I am looking forward to the upcoming challenges and many sweet memories that will be made in the next coming years. I hope to add to the positive and encouraging environment at CHRISTUS Santa Rosa. I am so excited and honored to be a part of the family!

I love trying new restaurants, especially brunch spots! Some of my favorite things to do when I have free time include getting my sweat on at the gym, dancing to hip hop music, throwing it down in the kitchen, and carpool karaoke with throwback/pop songs. On the weekends, I appreciate a slow morning getting ready before getting some Vitamin D in (with sunscreen, of course!).


A headshot of Alyson RandallAlyson Randall, DO

Hi and thanks for considering the CHRISTUS Santa Rosa Family Medicine Residency! I took a circuitous route to get here, but I know I am where I am meant to be. I am originally from rural Pennsylvania, the closest well-known town near my hometown being Gettysburg. I attended undergraduate education at University of Pittsburgh, at one of their smaller branch campuses. I entered the healthcare field as a Medical Service Corps Officer in the U.S. Army, a position in which I served for seven years at every major Army post in Texas. I then decided I wanted to be more involved in the frontlines of healthcare and more directly impact patient health, leading me to the University of the Incarnate Word School of Osteopathic Medicine, here in San Antonio. I enjoy and plan to continue to incorporate osteopathic principles and practice into my patient care.

I met and worked with several of the family medicine residents over the course of third and fourth-year clinical rotations. I was incredibly impressed with their depth of knowledge and ease with patient interactions, often confusing them with the specialty residents also on the rotation service. I am so excited to be learning in this full-spectrum, unopposed program in which I can tailor my education to the style of family medicine physician I hope to become. Growing up in a rural town where the family physicians did everything from deliveries to hospital medicine, I know I will be able to emulate them after completing this residency program!

Outside of medicine, I enjoy going on spontaneous adventures and seeing new places with my family of three kids, a dog, and two cats. I love trying new food and wine, experiencing other cultures, painting either oil or acrylic on canvas, and trying new physical activities. My all-time favorite sport is volleyball, so I am always up for a pick-up game! Golf, tennis, and basketball are close seconds. Self-care is very important to me, and I try to incorporate meditation, relaxation, and being immersed in nature into my life as much as possible.


A headshot of Esteban SosaEsteban Sosa, MD

Hi! I was born in Oklahoma, however, grew up in Brownsville, Texas. I attended The University of Texas Rio Grande Valley and graduated with a BS in Biomedical Science. I attended medical school at The University of Texas-Medical Branch (UTMB). I decided to specialize in Family Medicine because I wanted to have continuity with my patients.

CHRISTUS was a perfect match for me because I would be exposed to full-scope family practice while being surrounded by amazing people. I always loved to visit San Antonio and now I get to enjoy the city for the next 3 years.


A headshot of Zachary SumnerZachary Sumner, MD

I grew up in Frisco, TX, a not so small town in north Texas. I went to Texas Tech University where I met my wife and got a degree in microbiology. We then moved back to North Texas where I got my medical degree from the Texas College of Osteopathic Medicine.

I am very excited to be at CHRISTUS. As a family medicine doctor I wanted to be able to care for my patients at all times during their lives and CHRSTUS is a great place to learn.

In my free time I like to travel different places with my wife and hang out with our dog Avery.

I love spending time with my dog Pepino, playing video games, binge-watching shows on Netflix and exploring new restaurants.


A headshot of Nicole WellmanNicole Wellman, DO

I am originally from San Antonio and am happy to call it home. I graduated from Churchill High School (Go Chargers!) and then went to college at St. Edward’s University in Austin. I continued to live there for a couple of years and worked as a medical assistant before coming back to San Antonio to attend medical school at University of the Incarnate Word.

I am excited to join the CHRISTUS family and provide patient centered care to serve people in the city that I grew up in. I am passionate about women’s health and preventive medicine. I am looking forward to giving back to the community that gave me so much.

In my free time I enjoy hiking and spending time outdoors with my two dogs, Lily and Sosa. I also attend trivia pretty regularly and even win on occasion!

Third Year Residents 

A headshot of Anthony GallegosAnthony Gallegos, MD

Hello, and thank you for taking the time to read my bio! I grew up in Southern California where I spent much of my childhood in and out of the hospital, which inspired me to pursue a career in medicine. I started my higher education pathway at Allan Hancock College in Santa Maria where I conducted my first research project on neuroplasticity. I then attended UC Irvine (Go Anteaters!) where I majored in biology with a focus in neurobiology research, and where I met my wife, Briset. A few years later we took the leap of faith and road-tripped across the country to the University of Vermont for medical school where I discovered my love for motivational interviewing and good maple syrup. We started our family which includes our fur baby/dog Kobe, and our beautiful baby girl Elliana. When I’m not working, I enjoy going on walks with my family, listening to a good podcast or harry potter audiobook, or studying fantasy football stats.

I met the residents and faculty of CHRISTUS Santa Rosa at the AAFP national conference dinner. Right away, I felt like I was part of the family, and I knew I would love to work with this awesome group of people. I now have the privilege of gaining a well-rounded education at a program with Catholic values, serving a population where I can practice my Spanish, and becoming the best primary care physician I can be. We are so excited to call San Antonio our new home, and to raise our family in a family-friendly city with such rich Mexican culture!


A headshot of Nicholas GaskillNicholas Gaskill, MD

Hi! I grew up in Dallas and went to college in our nation’s capital to study Middle Eastern Studies and ended up graduating with a degree in Chemistry. I returned to Texas after graduating. I spent a year working as an EMT on an ambulance service from which I decided to pursue medicine. I also spent a year in biomedical research where I made an essential discovery in the mechanism of action of a cancer drug. After these experiences, I attended medical school in Houston.


A headshot of Rachelle HamblinRachelle Hamblin, MD, MPH

Hi All! I am originally from Livermore, CA, a small town about 1 hour inland of San Francisco. On my 14th birthday, while playing soccer, I had a Lis Franc injury, where I tore a ligament in my right foot, resulting in two surgeries and a year off. While my doctor wasn’t sure that I would be able to walk again without pain or compete, with the help of a great healthcare team and the support of my family, friends, and community, I was able to get back to the life I loved and even get recruited for college ball. Although I ended up not playing, opting to serve in the Naval Reserve Officers Training Corps (NROTC) at my #1 choice, UC Davis, instead, this injury ended up being a blessing and gave me a purpose and a passion to pursue medicine so that, I too, could serve and help others live the lives they love to their fullest. While there, I pursued a BS in Biology and worked as an intern at Sandia National Laboratories on a number of pathogen detection projects for the Department of Defense and Department of Energy. After college, I was incredibly blessed to be accepted into and attend my 1st choice medical school – UT Health San Antonio – as a dual degree MD/MPH (Masters of Public Health) student. People all the time ask why San Antonio from CA? This community fits me like a glove – the people here are amazing and go out of their way to help you. This “esprit de corps” has especially been prevalent during the COVID crisis and I’m so proud of our San Antonio community for stepping up and helping each other out to the best of our abilities.

I fell in love with Family Medicine on my 3rd year rotation with CHRISTUS. These were my people and I looked up to them and wanted to be like them. I enjoyed that I got to form long-term relationships with my patients, hear their stories, know them as people, and learn what was important to them so that I could better treat them. Beyond that, I had the ability to work with entire families, from babies to adolescents to adults to geriatrics, which is unique, and that I could also focus on prevention of illness and injuries. I’m very grateful to come full circle and attend my 1st choice residency here in San Antonio at CHRISTUS Santa Rosa. Not only do I get to stay and continue to work with my amazing San Antonio community, but I get to do so at a great, happy, supportive, well-rounded, and full-scope program with good people. I am so blessed.

In the future, I would love to be a community doctor who not only works in the community I live in, but is also an active part of it. I intend to use my MD/MPH to take care of my patients in and out of my clinic, doing community needs assessments and quality improvement/research projects and helping to teach and educate my community on injury and illness prevention using nutrition, sleep, and exercise as the basic foundations of health. To do so, I am working on getting certified in personal training, nutrition, and behavior change through that National Academy of Sports Medicine (NASM) and have gotten my Advanced Wilderness Medicine Life Support certifications. Beyond that, I am very interested in improving cancer awareness and prevention in our firefighters and am currently working with our San Antonio Fire Department (SAFD), MD Anderson Cancer Center, UT Health San Antonio, and our EMS Medical Director on a project to do so. In my “free” time, I enjoy training in krav maga, spending time with my family and friends, growing and taking pictures of plants (and now my fish), crocheting, and reading.


A headshot of Yen Linh KrantzYen-Linh Krantz, MD

Hello! I was born and raised in Austin, Texas to a family of UT Longhorns, but made my own way and graduated from Baylor University, where I was a member of Pi Beta Phi and ran Track & Field. I love to travel and have studied abroad in London, Greece, Turkey, Ecuador, and Bolivia. I moved to San Antonio in 2013, where I met my husband. We both graduated from UT Health San Antonio for medical and dental school. We have two dogs and enjoy spending time with them at the local dog parks.


A headshot of Juan LeuroJ.C. Leuro, DO

Hello! I was born in Colombia and moved to Texas when I was 7 years old! I grew up in Corpus Christi and Houston before graduating from The University of Texas at Austin with a degree in human biology. Hook ‘Em Horns!! I met my wonderful fiancée in Austin and she moved to Fort Worth with me to obtain her nursing degree while I completed medical school. Our family has now grown by two adorable pups, Nori & Remi, who we love to take on hikes and swimming in lakes!

I’ve had this dream of becoming a doctor since I was in 6th grade and it feels amazing to finally reach this point! I look forward to my time here at CHRISTUS Santa Rosa to develop into a great physician.


A headshot of David ParkerDavid Parker, MD

I was born and raised in a small East Texas town near Tyler. I completed my undergraduate education at Sul Ross University in Alpine, Texas and then attended medical school at the University of Texas Medical Branch in Galveston.

I was fortunate to get to work with a great full-spectrum rural doctor during my Family Medicine rotation. This instilled a passion in me for full-spectrum care and led to my discovery of the rewarding field of Sports Medicine.

CHRISTUS Santa Rosa is a great fit for me. It is a full-spectrum, “unopposed” program that offers great procedural training and exceptional Sports Medicine exposure. The faculty and staff are very accommodating in helping us tailor our learning experience to obtain the skills each of us need to be successful within our chosen niche.

In my free time, I enjoy building things, developing medical simulations, kayaking, hunting, and fishing in the beautiful Texas Hill Country with my wife and four children.


A headshot of Amanda ReinerAmanda Reiner, DO

Hey all you cool cats and kittens! I was born and raised in Mankato, Minnesota and attended college at the University of Wisconsin-La Crosse where I earned my Bachelor of Science degree majoring in Biomedical Science with minors in Nutrition and Chemistry. I then attended medical school at the Alabama College of Osteopathic Medicine in pursuit of becoming a Family Medicine physician. My passion for the specialty and holistic patient care has never wavered and still continues to grow.

I’m excited to start my next chapter here in San Antonio. CHRISTUS Santa Rosa is a perfect fit for me and my professional goals. It was a top-priority for me to be in an unopposed residency with full-scope training and even more important for me to feel at home with my colleagues as well as the community.

My interests include paddle boarding, fishing, multi-cultural cooking, pets (especially mine), and Marvel movies. My first passion before medicine was gymnastics, which I started at 6 years old. I competed for 12 years and coached for 5. My aching joints remind me of my first love every day.


A headshot of Humberto TrevinoHumberto Trevino, MD

I'm from Laredo, TX where I was born and raised. Medicine is something I have wanted to pursue since an early age due to a strong desire to help people and a love of science. My family was very supportive and helped me attend a health and science magnet high school which further developed my interest in medicine. Following this, I came to San Antonio to continue my studies at St. Mary's University where I earned my degree in Biochemistry. In my time spent at St. Mary's, their mission of helping the underserved was engrained in me and I began to volunteer at various organizations and causes in San Antonio. These experiences helped me understand the underserved populations and motivated me to continue helping them in the future.

The next chapter of my life led me to UTMB for medical school. This is where I discovered my passion for Family Medicine.

I am excited to be joining the Christus family and continuing a mission that is in line with both my faith and my personal ambitions.