William T. Chain Jr., 73, of Narberth, a doctor who succeeded his father as a respected internist on the Main Line, died Tuesday, Oct. 27, at Bryn Mawr Hospital after a yearlong battle with cancer.

Known as “Bill,” Dr. Chain was born in Philadelphia and raised in Narberth, the son of well-known family doctor William Thomas Chain and Elizabeth Wickwire Chain.

Dr. Chain was a 1965 graduate of Lower Merion High School, where he played varsity football and baseball and was a swimmer.

“He was a three-year starter on the baseball team at first base,” said Danny DeCrescenzo, an old schoolmate, in an online post. “His senior year, they were a championship team."

Dr. Chain earned a bachelor’s degree in 1969 from what is now La Salle University and a medical degree from Jefferson Medical College in 1973. He completed an internship in 1974 and a medical residency two years later at Bryn Mawr Hospital.

Dr. Chain began practicing internal medicine in Gladwyne in 1976 before purchasing his father’s former home and office on Windsor Avenue in Narberth in 1978 and moving his practice there. His father had practiced internal medicine in Narberth from 1946 until his death in 1971.

Both men were trusted physicians to hundreds of patients from the Main Line and bordering areas. Dr. Chain offered one service, however, that his father did not. In 1991, he earned certification in addiction medicine. A recovering alcoholic, he drew from his experience to lead others out of addiction.

“He was especially proud of his near three decades of sobriety and touched many lives, as he inspired and counseled others through their own struggles with addiction,” his family said in a tribute.

“He was an inspiration to many in recovery and a wonderful doctor,” Gary Hendler, of Ardmore, posted in an online message.

Former patients remembered Dr. Chain not only as a skilled practitioner but someone they could talk to easily.

“We spent a lot of time just talking about everything, not just medical issues. He really cared,” posted William McCarthy, of Narberth.

“We had a lot of fun trading Radnor/Lower Merion barbs and enjoying our sons' lives,” posted Jed Riddell, of Narberth. “A chunk of old Narberth is now missing.”

Dr. Chain met Christine Duncheskie while he was a medical student at Lankenau Medical Center, where she worked as a nurse. They married in 1973 and had two sons. His wife managed his practice from 1992 until his retirement in March when it became clear that his cancer was terminal.

The choice of medicine as a Chain family profession did not extend into the third generation. His elder son, William John Chain, is a professor of organic chemistry at the University of Delaware. His younger son, Matthew Chain, is a corporate lawyer in Los Angeles.

Dr. Chain coached CYO football for St. Margaret Parish, especially the seventh and eighth graders. In 1981, he was named coach of the year. He loved auto racing and went with friends as far away as Florida, Ohio, and Watkins Glen, N.Y., to watch the sport.

In addition to his wife and sons, Dr. Chain is survived by two grandchildren; two brothers; two sisters; and nieces and nephews. “He was overjoyed to welcome his first grandchildren this year,” his wife said.

A celebration of life will be held next spring. Interment will be private.

Memorial donations may be made to Shriners Hospital for Children in Philadelphia at 3551 N. Broad St., Philadelphia, Pa. 19140 or Providence Animal Center in Media at 555 Sandy Bank Rd., Media, Pa. 19063.