Medical Professionals

All professionals at maintain the highest levels of accreditation and pursue ongoing education to stay abreast of the latest trends in the medical field. Read on to learn more about our staff's experience and training.

Tanya R. Grun, M.D.

Dr. Grun is Board certified by the American Board of Family Medicine since 1992. She attended Angelo State University; graduated with a B.S. degree in Biology, Chemistry and Spanish in 1984. From there she earned her medical doctorate degree from Texas A&M University College of Medicine in 1989. Whoop!! Gig ’em Aggies! She then went on to do her residency at Memorial Medical Center Family Practice Residency Program in Corpus Christi, TX (1989-92).

After residency she was a member of the clinical teaching faculty at UTHSC-SA at Corpus Christi Residency Program (1992-95). She then practiced full spectrum Family Medicine (with surgical Obstetrics) (1992-2009) in Texas, Oklahoma and Tennessee.

In 2009 she moved to New Braunfels, Texas and started her private practice. She is no longer doing Obstetrics, but getting more sleep!!

Throughout her years of practice, she has had a special interest in working with underserved populations (mission fields in MX/Costa Rica/Nigeria; rural prenatal care/OB services; addiction treatment, etc.) She also has a special interest in the appropriate diagnosing and treatment of ADD/ADHD in children and adults.

Dr. Grun is dedicated in providing high quality patient care to all of our patients—newborns to geriatrics. She believes strongly that having care (preventive/acute/chronic mgt) from a trusted primary care provider is vitally important in maintaining good health through one’s life.

She loves living in the country outside of New Braunfels, TX. She enjoys traveling, photography, music, and a variety of animals at home. She also loves spending time with her two beautiful daughters and having LOTS of fun with her 3 awesome grandkids! Favorite color: PURPLE. Favorite food: CHEESE.


Sierra Santellana, PA-C

Sierra Santellana is a physician assistant certified through the National Commission on Certification of Physician Assistants. She joined our practice in January 2013. She is originally from Edna, Texas.

She obtained her Bachelor of Arts degree in Biology from Texas Lutheran University in Seguin, Texas in 2010 and her Master of Physician Assistant Studies degree from the University of Texas Medical Branch in Galveston, Texas in 2012. She has practiced in family medicine since graduating and has grown to love family medicine and taking care of patients of all ages.

She has practiced in family medicine since graduating and has grown to love family medicine and taking care of patients of all ages.

She lives in New Braunfels with her husband, Orlando, and their daughters, Lexi and Lainee. She enjoys spending time with her family and she is a dedicated Dallas Cowboys fan.


Teri Kelso, LVN, Clinical Director

Bio Coming Soon...


Holly Chapman, Nurse Practitioner

Holly Chapman is board certified through the American Academy of Nurse Practitioners. She is a member of Texas Nurse Practitioners and Hill Country Nurse Practitioners Association. Formerly, she earned her Bachelor of Science degree in 2012 and later passed the National Counsel of Licensure Examination (NCLEX). Beginning her career as a registered nurse at Baylor Hospital in Dallas, Texas, Holly worked as a bedside registered nurse while completing her Master of Science- Family Nurse Practitioner degree at Texas Woman’s University in 2017.

Prior to joining Abundant Health!, Holly worked as a Nurse Practitioner in family medicine. During which she also volunteered her time on mission trips and at an uninsured clinic. Her passion is influencing patients’ lives by encouraging a healthier lifestyle for a more Abundant life!

Originally from a small town in deep east Texas, she currently lives in New Braunfels with her husband, Jaret. In her spare time, Holly enjoys all things in the great outdoors and the adventures of traveling. You will most often find her spending time with her large family, exercising, trying out new ice cream shops, or hanging with friends.