The park is named for the three Zalewski brothers – Stanley, Charles and Anthony – two of whom served in World War II.
Stanley, 20, was killed in action on July 19, 1944.
"My uncle was writing a letter to my mom [Mary] while he was in a foxhole in France," said nephew Glenn Stewart, 53, of Cliffside Park. "He was trying to meet his brother, Tony, in England.
"By the time she got the letter he was killed."
Charles never served overseas after he was injured by his gun's recoil, Stewart said.
Mary Stewart (nee Zalewski), 90, made the trip from Forked River to attend along with other family members.
The playground area of the park was expanded and a new surface, swings and other equipment were added. The work was completed by brothers Elias and Tony Nehme.
Mayor Thomas Calabrese addressed the crowd before cutting a red ribbon.
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