Dubbed "The Boy in the Box" or "America's Unknown Child" after his body was found stuffed in a bassinet box along Susquehanna Road in February 1957, the boy's case was one of the oldest unsolved murders in Philadelphia history, according to the department.
Zarelli was born in 1953, and police say they have identified his parents. Officials said they were able to identify the boy by comparing his DNA samples to those logged in genealogical databases.
Commissioner Danielle Outlaw said the case is still an active homicide investigation, and that detectives are still working to identify his killer.
Retired Det. Sgt. Bob Kuhlmeier previously said that the cause of death was blunt force trauma, according to CBS3.
A recent DNA sample linked the boy, between ages 4 and 6, to a family in Delaware County, NBC10 reports.
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