Sullivan ran a butcher shop for 25 years in Queens, where he was raised. He had close relationships with most of his customers, said his son, Tom of Huntington, who as a youth was a delivery boy for Sullivan's Meat Market.
"They would confide in him many of the troubles they faced in their personal lives," Tom Sullivan said. "There used to be a private spot at the end of the counter where my father would often bring the customer to have a more private discussion. When this occurred, the rest of the butchers in the store used to say, 'Tom is hearing confession.' "
He enlisted on Dec. 26, 1941, after the Pearl Harbor attack.
Sullivan was born in Bay Ridge, Brooklyn, the son of Irish immigrants.
He married the former Doris Archer on Thanksgiving 1945, after returning from the war. The two would have celebrated their 67th anniversary this year.
Patricia said the couple were "truly in love," and after he became ill, the relationship strengthened.
"It was a vibrant love," she said. "They were truly engaged. It was a beautiful love story." There were only nine days when the couple did not see each other, mostly because he was traveling, she said. "They shared a life together."
The couple lived in Wantagh for many years.
Sullivan ran the butcher shop in Queens from 1957 to 1983. After that, he did volunteer work for Mercy Medical Center in Rockville Centre and St. Frances de Chantal Church in Wantagh, family members said.
Patricia Sullivan, who teaches history at the University of South Carolina, said her father inspired her to become a historian.
"It grew out of hearing his stories," she said. "He was a great storyteller."
Besides his wife, son and daughter, Sullivan is survived by a half-brother, Michael, of Middleton, N.J.; daughters Kathleen Basil, of Uniondale, Mary Sullivan Lester, of East Northport, and Eileen, of Brooklyn; and seven grandchildren.