Mary (Walsh) Dennehy, 89, a Dorchester native and longtime Braintree resident, died peacefully on March 2, 2026, after a brief illness, in her daughter Denise’s home on Cape Cod, surrounded by her five children.

Mary was born on Nov. 27, 1936, the first of five daughters to the late Patrick J. and Margaret A. (McSweeney) Walsh. She treasured growing up in Boston, where her family lived, at different times during her childhood, in the neighborhoods of Neponset (Dorchester), South Boston, and East Boston, and where she attended parochial schools.

But Neponset, where she was born and would later return, was the place she cherished most. From the age of 13 until she was 20, Mary, with her parents and sisters, lived on Plain Street, in St. Ann’s parish. For the rest of her life, she spoke with deep affection about those days: the close-knit community where all the families knew each other and where a young girl could walk freely from door to door; trips with her friends to Garvey Playground and Howard Johnsons; and summer days on Tenean Beach (where her parents met two decades earlier). And then later, CYO dances and “record hops,” where she and her friends would dance to Elvis Presley and Fats Domino.

It was also in Neponset where she met the girls who would become her lifelong friends, her beloved “Club,” who remained close throughout the rest of their lives.

In summers, Mary and her sisters would travel to Cape Cod to assist her revered uncle, Father James “Jimmy” Walsh, and his fellow priests, during their annual vacations. The girls’ duties included serving as caddies while the priests golfed; somehow Mary, going against her nature, remained silent as they played.

In 1954 she graduated from the former Mount Saint Joseph Academy, in the city’s Brighton neighborhood, and then began work at the Boston law firm Nutter McClennen & Fish.

Three years later, in the summer of 1957, Mary met Jack Dennehy, a Boston College student who’d just returned home after serving in the U.S. Army. On that afternoon, Mary and her friend Barbara Foley had just finished praying a novena at St. Ann’s church when Barbara’s boyfriend (and future husband), Charlie Pickering, picked them up for dinner at Howard Johnsons.

“When he picked us up, Charlie said, ‘My cousin just got back from the service. Instead of going to Johnsons, maybe we can go out somewhere and have a pizza?’” Mary later remembered. Soon they were in nearby Milton, where Charlie’s cousin Jack came jogging out of his family’s house, in white bucks and trailed by his dog Pal. “He jumped in the back seat, and we went and had pizza,” she said. “I know Barbara and I giggled all night.”

Mary and Jack were married on August 8, 1959, at St. Brendan’s Church in Dorchester. A year later, their first child, Mary Ellen, was born in Dorchester. In 1962 they moved to Braintree, where they had four more children — John, Denise, Jill, and Kevin — and where they would live together for 54 years. She’d often say she was never happier than when she had three kids in diapers.

For more than two decades Mary worked as a legal secretary in the New England Telephone Company’s Franklin Street office, in Boston, serving as a union steward representing fellow employees for several of those years.

Throughout her years in Braintree, Mary was an active member of the former St. Thomas More parish, where her four youngest children were baptized. In the 1970s, Mary and Jack were part of a large group of parish families that created an offshoot “community” that advanced a more modern catechism for the parish — a period when Masses were celebrated offsite by priests from Boston College High School and CCD classes were taught in the homes of parishioners — and which would help reshape the parish culture, including the creation of a new “team ministry” by the decade’s end. Over the years, Mary also taught CCD at St. Thomas More, was a member of the Ladies Sodality, the Couples Club, and was a Eucharistic Minister of Holy Communion.

After retiring from New England Telephone in 1995, Mary took on a new role as St. Thomas More’s parish secretary. She enjoyed her role assisting the many priests and clergy in coordinating church affairs. (She also relished being able to keep up with the latest parish gossip.) In the parish offices, she was always willing to assist and was well-known for her kindness, feisty manner, honesty, and quick wit.

In 2017, after the death of her beloved husband Jack, Mary moved to Independence Manor in Braintree, where she was able to nurture relationships with neighbors she’d known for years — and to create new friendships. As ever, she had a keen eye for those with Dorchester roots. “As a rule, they’re the best people,” she’d often say (only half joking). She’d also keep a close eye out for those residents who needed assistance, often escorting neighbors back to their rooms to make sure they made it home safely.

Most of all, Mary remained forever devoted to her family, especially her cherished children and grandchildren, and treasured every chance to gather with her family, including for 50 years in her home on Wilson Avenue.

She was the beloved wife for 56 years of the late John A. “Jack” Dennehy; devoted mother of Mary Ellen Dennehy of Braintree, John A. Dennehy and his wife Patricia of Yarmouth Port, Denise J. Carlson and her husband Keith of Harwich, Jill M. Carr and her husband Brian of Plympton, Kevin B. Dennehy and his wife Lauren of Guilford, Connecticut; and loving grandmother of Courtney Moores (Jason Adams), Timothy Moores, Erin Dennehy, Shannon Dennehy (Samuel Carthy), Jaclyn Dennehy, Connor Carlson, Cameron Carlson, Nolan Carr (Inna Carr), Devan Abi-Elias (John Abi-Elias), Caitlyn Carr, Jack Dennehy, and Sean Dennehy.

The oldest of five siblings, Mary was the dear sister of Nancy Buck and her husband Robert Buck of Severna Park, Maryland; Peggy Curtis of Charlottsville, Virginia, and her late husband Walter; Kathy Lavin of Weymouth and her late husband James; and the late Ellen Barry and her late husband Joseph.

Mary is also survived by dozens of nieces, nephews, and their families.

Visiting Hours will be held at the Sweeney Brothers Home for Funerals, 1 Independence Avenue, Quincy, on Sunday, March 8, from 2 – 5 p.m. Relatives and friends are invited to attend. A Funeral Mass will be celebrated in Saint Francis of Assisi Church, 856 Washington Street, Braintree, on Monday, March 9, at 10 a.m. Interment will follow at Milton Cemetery.

For those who wish, donations in Mary’s memory can be made to the Dana-Farber Cancer Institute, P.O. Box 849168, Boston, MA 02284 or www.dana-farber.org.