Dion DiMucci, the lead singer who left the Belmonts in 1960, said on his Facebook page Tuesday, "May he rest in peace and rock on in heaven."
Milano and three friends from the Bronx formed the Belmonts in the mid-1950s, borrowing their name from the borough's Belmont Avenue. They became Dion and the Belmonts after DiMucci joined in 1958.
Milano sang tenor on hits like "A Teenager in Love" and "Where or When."
The Belmonts continued to perform and to record with different lineups after DiMucci left for a solo career. Gradus said Milano was performing with the Belmonts at casinos and other venues just weeks ago.
There was strife between DiMucci and Belmonts members, who were not pleased when DiMucci was inducted into the Rock and Roll Hall of Fame without them in 1989.
In his Facebook posting, DiMucci said Milano "was very savvy with harmonies" and added, "We had our ups and downs through the years but that's how things go in families, even rock-and-roll families."
Milano went back school in middle age and joined the Department of Correction in 2003.
In his position as a legal coordinator at the Rikers Island jail complex, he helped inmates research their cases and taught a legal research class, said Karen Powell, director of law libraries for the department.
Powell said Milano had more energy than colleagues two decades younger and "was a person who really loved life."
"We'd know it was him coming through the door because we'd hear him singing and skipping up the stairs," Powell said.
Milano is survived by his wife, Lynn, two children and 10 grandchildren.
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