John M. Walker

John Mercer Walker Sr. was born on January 15, 1907, and died on August 16, 1990. He was an American physician and investment banker. Walker was a member of the Bush-Walker family and was related to U.S. President George H. W. Bush as a maternal uncle.

Walker was the fifth of six children of George Herbert Walker, a banker and businessman, and his wife Lucretia Wear, the daughter of James H. Wear. His older sister Dorothy married Prescott Bush, who was a U.S. Senator and the father of President George H. W. Bush.

For his early education, Walker attended The Hill School. He later studied at Yale University, where he graduated in 1931. During his time at Yale, he participated in athletics, lettering in football, baseball, and squash. He was also a member of the secret society Skull and Bones.

In 1936, Walker graduated from the Columbia University College of Physicians and Surgeons. He completed his residency at Roosevelt Hospital. In 1939, he married Elsie Louise Mead, daughter of George Houk Mead, who served as president of the Mead Corporation. They had a total of seven children: three sons and four daughters. One daughter died of polio in 1955, and two daughters were born with Down syndrome.

During World War II, Walker served as a major in the United States Army in Europe. He practiced medicine privately until 1950, when he was diagnosed with polio, which resulted in the need to use a wheelchair, despite his prior athletic ability and skill as a golfer.

In 1952, Walker joined Memorial Hospital, now part of Memorial Sloan–Kettering Cancer Center, as a clinical assistant in surgery. He remained there for 25 years and served as president from 1965 to 1974. In 1953, President Bush’s daughter, Pauline Robinson "Robin" Bush, was diagnosed with leukemia. A local doctor considered treatment futile, but Walker helped facilitate her admission to Memorial Sloan–Kettering. She lived approximately six more months and died shortly before her fourth birthday.

President George H. W. Bush later described Walker as a skilled cancer surgeon who had experienced polio himself and characterized him as a strong and purposeful individual. Walker's advice and efforts in Robin Bush's treatment were noted as being influential, reflecting his commitment to progress in cancer care.

After his medical career, Walker pursued a second career as an investment banker. He became a managing partner at G. H. Walker & Co., the firm founded by his father in 1900, and also held a limited partnership at Alex. Brown & Sons. In 1971, he retired to a farm in Easton, Maryland, which he operated profitably for approximately twenty years.

Walker also spent summers in Kennebunkport, Maine, with his extended family. In 1989, U.S. President George H. W. Bush appointed Walker’s eldest son, John M. Walker Jr., as a District Judge on the United States Court of Appeals for the Second Circuit. President Bush remarked that the appointment was a gesture of gratitude to Walker's family, noting his son’s qualifications.

John Mercer Walker Sr. died in 1990 due to an aneurysm in Kennebunkport.