Our Leadership Team

At Children’s Memorial Hermann Hospital, providing the highest quality health care to our young patients and their families is our top priority. To do that, we hire the best. Our affiliated physicians, nurses, hospital staff and every other member of our team reflect our high standards of care. Our executive leadership team is another example of these high standards. Each member of our leadership team is highly qualified and respected in the fields of health care, exemplary patient care as well as best-in-class hospital operations.

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Guy B. Giesecke, DHA, FACHE

Senior Vice President and Chief Executive Officer, Children’s Memorial Hermann Hospital

Guy B. Giesecke, DHA, FACHE, serves as Senior Vice President and Chief Executive Officer of Children’s Memorial Hermann Hospital, where he provides strategic and operational leadership for one of the nation’s leading pediatric health systems. With nearly two decades of executive experience in pediatric and academic health care, Dr. Giesecke is recognized for leading transformational growth initiatives that expand access to high quality, specialized care for children and families.

Dr. Giesecke joins Children’s Memorial Hermann Hospital after nearly 15 years at the University of Mississippi Medical Center (UMMC), where he served as Chief Executive Officer of Children’s of Mississippi. During his tenure, he led significant growth and modernization efforts, including the planning, design and construction of a 360,000-square-foot expansion that more than doubled the hospital’s size. Under his leadership, Children’s of Mississippi expanded its statewide network of outpatient specialty clinics, strengthening access to pediatric care across Mississippi.

Throughout his career, Dr. Giesecke has demonstrated a strong commitment to quality, safety and patient experience. At UMMC, he helped establish systems that exceeded national benchmarks in pediatric outcomes, patient safety and patient experience, while also advancing value-based care partnerships and regional referral growth. His leadership supported meaningful increases in surgical volume, outpatient access, and complex pediatric services.

Prior to his tenure at UMMC, Dr. Giesecke served as Chief Operating Officer at Baptist Hospitals of Southeast Texas and as Vice President at East Texas Medical Center in Tyler, Texas. Earlier in his career, he held multiple leadership roles at Driscoll Children’s Hospital and began his health care career with Memorial Hermann Health System, providing him with a longstanding connection to the organization and its mission.

Dr. Giesecke is a Fellow of the American College of Healthcare Executives and an active national health care leader. He serves on the Boards of Directors for the Children’s Hospital Association and Solutions for Patient Safety, contributing to national efforts focused on advancing pediatric quality and safety.

He earned his bachelor’s degree in business administration from Abilene Christian University, a master’s degree in health care administration and business from the University of Houston–Clear Lake, and a Doctor of Health Administration from the University of Mississippi.

Emily Weber, DNP, RN, CPN, NEA-BC

Vice President and Chief Nursing Officer/Operations, Children’s Memorial Hermann Hospital

Dr. Emily Weber, DNP, RN, NEA-BC, is Chief Nursing Officer and Vice President of Operations at Children’s Memorial Hermann Hospital, a 332-bed quaternary women’s and children’s hospital in the Texas Medical Center and a designated Level IV maternal care facility and Level IV NICU.

A seasoned healthcare executive with more than 25 years of experience, Dr. Weber previously served as Chief Nursing Officer within a large health system and held progressive leadership roles at one of the nation’s largest freestanding pediatric hospitals. Across her career, she has led maternal–child health, neonatal intensive care and pediatric service lines, bringing deep expertise in nursing strategy, clinical quality, operational performance and regulatory excellence.

Dr. Weber oversees nursing practice and hospital operations, advancing strategic initiatives that drive quality outcomes, workforce engagement and organizational performance. She is known for building high-performing teams and cultivating leadership cultures grounded in accountability, innovation and compassionate care.

She earned her Doctor of Nursing Practice from UTHealth Houston, her Master of Science in Nursing from Texas Woman’s University, her Bachelor of Science in Nursing from The University of Texas Medical Branch and her Associate Degree in Nursing from Alvin Community College. She is board certified in pediatrics and nursing administration–advanced.

Outside of her professional responsibilities, Dr. Weber values time with her husband of 26 years, her two daughters and her son-in-law, and enjoys running outdoors.

Sean C. Blackwell, MD

Chief of Service, Obstetrics and Gynecology, Children’s Memorial Hermann Hospital; Professor and Chair, Department of Obstetrics, Gynecology and Reproductive Sciences

Dr. Sean Blackwell is the Chief of Service for Obstetrics and Gynecology at Children’s Memorial Hermann Hospital. In this role, he has been instrumental in developing a robust obstetrical and gynecological program at McGovern Medical School at UTHealth and in the Memorial Hermann Health System. Dr. Blackwell drove the development of The Fetal Center, and has aggressively expanded the high-risk pregnancy clinics throughout the Greater Houston area, now with nine clinic locations across the city. Under his leadership, the department of Ob/Gyn has developed a team-centric approach anchored in collaboration and a dedication to serving patients, as well as excellence in medical education and research.

Dr. Blackwell has been the principal investigator for Eunice Kennedy Shriver National Institute of Child Health and Development (NICHD) Maternal Fetal Medicine Units Network at McGovern Medical School at UTHealth (2007-2011), which is the largest clinical trials network in the United States. UTHealth is one of only eight institutions that have both the NICHD-funded maternal and neonatal research networks. In 2014, Dr. Blackwell earned his Six Sigma-Lean Black Belt at the University of Houston, allowing him to apply continuous quality improvements in operational processes to achieve predictable and measurable results.

He directs the Larry C. Gilstrap M.D. Center for Perinatal and Women’s Health Research at UTHealth and serves as the assistant dean for Healthcare Quality in Perinatal Medicine and Women's Health. He is a graduate of the Physician Quality and Safety Academy at Memorial Hermann-Texas Medical Center and McGovern Medical School at UTHealth. Blackwell served as the vice chair for the Society of Maternal Fetal Medicine (SMFM) Publications Committee and on the SMFM board of directors.

Dr. Blackwell obtained his undergraduate degree as a double major in biology and classics at Wabash College in Crawfordsville, Indiana. He completed medical school at the University of Illinois College of Medicine in 1993 and completed both his obstetrics and gynecology residency and maternal-fetal medicine fellowship at Wayne State University in Detroit, Michigan.

Kevin P. Lally, MD

Surgeon-in-Chief, Children’s Memorial Hermann Hospital; Professor and Chairman, Department of Pediatric Surgery

Dr. Kevin Lally is the Surgeon-in-Chief at Children’s Memorial Hermann Hospital and the Chair of the Department of Pediatric Surgery at McGovern Medical School at UTHealth. In his role, he has built and recruited for the hospital’s pediatric specialty services and continues to expand the programs within the surgical program, including General and Thoracic Pediatric Surgery, Pediatric Plastic and Craniofacial Surgery, Pediatric Neurosurgery, Pediatric ENT, Pediatric Cardiovascular Surgery, Pediatric Orthopedic Surgery, Pediatric Urology and Pediatric Trauma.

Board certified in pediatric surgery, surgical critical care and general surgery, Dr. Lally’s clinical interests include prenatally diagnosed problems and congenital diaphragmatic hernia (CDH) as well as Extracorporeal Membrane Oxygenation (ECMO). Dr. Lally, who has published more than 200 scientific articles with over 70 about basic science and clinical research on CDH, helped found the CDH Study Group and the CDH Registry. The voluntary collaborative has gathered data on more than 9,000 babies with diaphragmatic hernia. The registry now represents centers in 14 countries.

Dr. Lally is a distinguished graduate of the US Air Force Academy and an AOA graduate of Tulane University Medical School in New Orleans, Louisiana. He completed his residency at the United States Air Force Medical Center at Keesler Air Force Base, Mississippi, and a fellowship at Children’s Hospital of Los Angeles. Dr. Lally holds the Richard Andrassy, MD, Endowed Distinguished Professorship and the A.G. McNeese Chair in Pediatric Surgery at McGovern Medical School at UTHealth. He has been recognized by the Houston Surgical Society with the Distinguished Houston Surgeon-of-the-Year award, with UTHealth’s President’s Award for Mentoring Women, as well as UTHealth’s Teaching Excellence Award and Outstanding Surgical Educator award. He is a member of the American Pediatric Surgical Association, the American Academy of Pediatrics and is a fellow of the American College of Surgeons (ACS) and serves on the Advisory Council for Pediatric Surgery. 

Mary E. Aitken, MD, MPH, FAAP

Pediatrician-in-Chief, Children’s Memorial Hermann Hospital and Chair, Department of Pediatrics, McGovern Medical School at UTHealth

Dr. Aitken is Pediatrician-in-Chief at Children’s Memorial Hermann Hospital and Chair of the Department of Pediatrics at McGovern Medical School. Dr. Aitken joined McGovern Medical School in 2019 with the goal of building on the tradition of clinical and educational excellence of the pediatrics program, which combines quality-focused, cutting-edge care at Children’s Memorial Hermann Hospital and a network of primary care training sites and subspecialty pediatric clinics, including UT Physicians, across the Houston community. She is expanding the research capacity of the department to include not only basic and clinical science, but with a focus on population health for children. Dr. Aitken holds the Dan L Duncan Distinguished University Chair in Pediatrics and serves on the Clinical Leadership Council Governance Committee for UTHealth.

Dr. Aitken is a board-certified pediatrician who has devoted much of her career to the study and promotion of injury prevention for children. In her previous appointment at the University of Arkansas for Medical Sciences, Dr. Aitken was professor of pediatrics, interim president of the Arkansas Children’s Research Institute, vice chair for research for the University of Arkansas for Medical Sciences Department of Pediatrics, and interim section chief of General Pediatrics. She also led the Center for Applied Research and Evaluation from 2006 through 2019 and directed the Injury Prevention Center at Arkansas Children’s Hospital.

Dr. Aitken received funding from the National Institutes of Health, Centers for Disease Control and Prevention, and other federal, state, and private agencies to support her injury prevention research in motor vehicle safety, all-terrain vehicle (ATV) safety, and safe sleep in high-risk populations. Her clinical, educational, and advocacy efforts have been focused on prevention as well as treatment of acute and chronic conditions of childhood.

A graduate of the University of North Carolina School of Medicine, Dr. Aitken completed a pediatrics residency at The Johns Hopkins Hospital. She also completed a master’s degree in public health with a concentration in epidemiology during a general academic pediatrics fellowship at the University of Washington. She is the recipient of numerous awards including the Fellow Achievement Award of American Academy of Pediatrics Council on Injury, Violence, and Poison Prevention. She is a Fellow of the American Academy of Pediatrics and a member of the Society for Pediatric Research, American Pediatric Society, and the Society for Violence and Injury Research.