Thomas and Ruth O’Brien, longtime Brookline residents and parents of comedian Conan O’Brien, both died this week at their Brookline home. Thomas, who was 95, died on Monday, December 9th, and Ruth died on Thursday, December 12th, aged 92.

According to an obituary published in the Boston Globe, Thomas O’Brien was the first director of the Division of Infectious Diseases at what is now Brigham and Women’s Hospital. He is known for raising awareness of the risks of antimicrobial resistance – a problem that makes it difficult to treat infections – and is co-founder of a research initiative that is now used in more than 130 countries, the Globe reported.

“For the rest of my time on Earth, I will hear from people who want to talk to me about my father,” Conan O’Brien told the Globe. “I’ve never met anyone like him, and he happens to be my father. If I happened to meet him in a hotel lobby, I’d think, ‘Who the hell is this guy?’ He’s the most interesting person I’ve ever met.'”

Thomas O’Brien worked at Brigham and Women’s and Harvard Medical School for more than 60 years before retiring in 2019 at the age of 90.

He was born on January 28, 1929 in Worcester to Francis Noonan O’Brien and Gertrude Connor O’Brien. He graduated from Mary E. Wells High School in Southbridge in 1946 and attended the College of the Holy Cross, where he earned a bachelor’s degree in classics in 1950. He then attended Harvard Medical School, completed his residency at Peter Bent Brigham Hospital, and had an immunology fellowship at the University of Cambridge in England before serving in the Army Medical Corps in San Antonio for two years, according to the Globe.

He married Ruth Reardon, a sister of two of his Holy Cross classmates, in 1958, the Globe reported. They moved to Brookline in 1963.

According to her obituary, Ruth O’Brien (née Reardon) was a real estate attorney at the Boston law firm Ropes & Gray and only the second woman ever to be a partner at the firm. Prior to Ropes & Gray, she was a law clerk for Raymond Wilkins, Chief Justice of the Massachusetts Supreme Court.

Ruth O’Brien was born on December 16, 1931 in Worcester to James Francis Reardon and Ruth Powers Reardon. According to her obituary, she graduated from South High School in 1949. She went on to earn degrees from Vassar College in 1953 and Yale Law School in 1956. At Yale, she was one of only four women in her law school class and was elected vice president of student government, her obituary said.

Thomas and Ruth O’Brien were married for 66 years. They are survived by six children – Neal, Luke, Conan, Kate, Jane and Justin – nine grandchildren and 15 nieces and nephews.

A funeral mass for Thomas and Ruth O’Brien will be held at 11 a.m. Dec. 18 at St. Lawrence Church in Brookline. The viewing will be held at the church on December 17th from 3 to 7 p.m. Burial will follow in Walnut Hills Cemetery.