As if he knew his life could not be confined by a mind that never grew out of childhood, Jack Brett would go for long walks as a boy in Dorchester, favoring routes with straight streets where he could gaze ahead, several blocks into his future.
A police officer might encounter him a couple of miles away and chauffeur Mr. Brett home, where his siblings would watch him approach, happy for a ride in a cruiser.
Some leave their mark through work and accomplishments. Mr. Brett left his by inspiring his family, including his youngest brother, who spent years in the Legislature championing the causes of constituents whose political voices are often only a whisper.
“People say to me, ‘How did you get involved as an advocate for people with disabilities?’ I’d say it was my brother Jack who was my greatest inspiration,” said his brother Jim, a former state representative from Dorchester. “I looked with awe at how he was able to overcome his challenges day to day.”
Mr. Brett, the oldest child in a family that became well-known in Boston, died Sunday in South Shore Hospital in Weymouth of complications from an infection. He was 76 and lived in a group home in Scituate.
“Our lives were shaped by the way Jackie lived his life,” said his sister Peg Brett McCobb of Weymouth. “It seems like because of him, everyone in the family has a soft spot for the underdog. Your heart goes out to people who are disadvantaged and you reach out to them. We do favors for people, but always with Jack in the back of our minds.”
Bill Brett of Hingham, former chief photographer of the Globe, called his older brother “the nucleus who kept our family strong.”
With a brother in the media and another on Beacon Hill, Mr. Brett traveled in circles that gave him a higher profile than many who are developmentally disabled. Because he had the ear of a legislator who later became a mayoral candidate, he also had clout.
Once when the Legislature debated votes on social service spending, Jim stepped outside the State House to find his brother among those protesting potential cuts.
“He said, ‘James’ -- he was the only person in the world who called me James -- ‘you'll do the right thing,’ ” Jim said.
When John Patrick Brett was born in 1934, a doctor predicted he would not live past 25.
“My mother was told by the doctor, ‘My best advice to you is to put him into an institution because he’s not going to live very long,’ ” Jim said. “She refused and brought him home.”
Accustomed to shouldering responsibility, Mary Ann Brennan was born in a farm family in County Sligo, Ireland, and immigrated to the United States, where she married Henry Brett and settled in Boston. She scrubbed floors at a bank in the middle of the night so she could spend each day at home looking after her six children. The youngest five, in turn, looked after Jack.
“You know, he wasn’t always treated well by other children, but there was always one of us to defend him,” his sister said.
During their mother's later years, McCobb said, “every Sunday the five of us would go up to visit her for a cup of tea, and she’d say, ‘I wonder what’s going to happen with Jack?’ We would say, ‘Don’t worry, we’ll take care of him.’ ”
When Jim campaigned for his first legislative term, he lived in the same Dorchester building with his mother and Jack.
“I went upstairs to check on them, and my mother was on the floor,” Jim said. “She had suffered a stroke, and there was my brother Jack with a pillow under her head, trying to help her and comfort her. After that he’d say, ‘I know I’m going to heaven because I tried to help my mother.’ ”
Mr. Brett, whose father died in 1977, was able to run errands and take rudimentary care of his needs. But when his mother died in 1981, he required additional assistance, so he moved to an Ashmont nursing home. Then, he lived in group homes in Dorchester and Quincy before settling in Scituate.
Just as during his childhood, Mr. Brett enjoyed being outside as an adult.
“He would walk four or five miles a day,” his sister said. “He was a great, great walker and just a nice person, you know? Everybody knew him because he said hello to everyone.”
Perhaps because of his daily jaunts, Mr. Brett was fascinated by TV weather reports and could rattle off the forecast for the next few days. And he had a high tolerance for physical discomfort, even when illness left him bedridden.
“I talked to him a couple of weeks ago on his birthday and asked him, ‘How do you feel, Jack?’ and he said, ‘In the pink,’ ” Bill recalled. “He was always ‘in the pink.’ ”
Mr. Brett’s presence and demeanor kept his siblings feeling good, too.
“I feel so grateful to have had him for a brother because of the gift he gave all of us to be so close together,” his sister said.
“He would see things that I wouldn’t see, and he would remind me of the simple things in life,” Jim said. “He was genuine, a very simple person in the sense of not having any of the qualities that most people have like anger and jealousy. He had none of that. I’ve often said that of the family, he was the closest to God from the day he came into this world because of his simplicity.”
In addition to his sister Peg and his brothers Jim and Bill, Mr. Brett leaves another brother, Harry of Braintree, and another sister, Mary McCarthy of Quincy.
A funeral Mass will be said at 10 a.m. Thursday in Blessed Mother Teresa of Calcutta at St. Margaret Church in Dorchester.
Mr. Brett will be buried next to his mother in Cedar Grove Cemetery in Dorchester, where beneath her name on the gravestone is the inscription, “and her special son, John P. 1934 -- 2010.”
“I once sat with him,” Jim said, “and I asked, ‘Jack, do you ever think about when you pass on what will happen to you?’ He said, ‘I’m not afraid. Two things will happen. One, I will go to heaven, and two, I’ll get to see my mother.’ ”
Bryan Marquard can be reached at email@example.com.
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