Thomas J. Kelly Jr. was a dockbuilder who worked on major projects at the Lincoln Tunnel and the Sag Harbor/North Haven bridge and other sites, but his family said Kelly also took pride in helping to build the character of young people.

“For a good 15 years he ran the Junior Naval Reserve of America in Wantagh,” his sister Eileen said, “so young children would learn about the Navy – get a sense of commitment, values and service.”

Kelly, 60, a former U.S. Navy petty officer, died last week after a heart attack at his home in Seaford. Services were held Saturday at St. William the Abbot R.C. Church in Seaford.

Born in Brooklyn, Kelly moved to Wantagh in the 1960s where he graduated from Wantagh High School. He later earned an associate degree from Nassau Community College.

Kelly enlisted in the Navy after high school and was a petty officer aboard a destroyer, the USS Charles R. Ware, serving as a radio technician in the Mediterranean.

Most of his work life was spent as a dockbuilder. They generally install heavy timbers and weld or cut large metal beams, working with large equipment and heavy materials. They’re seen driving in metal sheet pilings to hold back the dirt during excavations.

As a member of Dockbuilders Local Union 1456 in Manhattan he worked on construction projects at the Lincoln Tunnel in the 1980s, the Newtown Creek treatment plant in Greenpoint, the Wantagh Parkway Bridge and the bridge connecting Sag Harbor and North Haven. Much of his recent work was done for John P. Picone Construction in Lawrence.

Kelly loved to travel when he was not working, but for years, much of his time at home was spent volunteering, his family said, particularly with young people.

He was a mentor for future sailors for many years through the Wantagh battalion of the Junior Naval Reserve of America, known as Sea Cadets, and was commandant of that local group for many years.

“Tom knew the true definition of giving and unconditional love,” said Ken Wharton, who as a youth in the 1970s was a member of Kelly’s Sea Cadets. “I would call him my second father . . . He left a great legacy of love and friendship.”

In addition to his sister Eileen, he is survived by brothers John, Dennis and Francis and another sister, Anne Conlon, all of Seaford.