"Bill was dedicated to the mission and success of this order of 'Blessed Little Sisters' - as he called them - for all his life," his family said in a tribute. They in turn called him "Papa Bill."
As a third-degree Knight, Mr. Kelly was active in the charities of the Knights of Columbus. He was especially glad when the group helped those overlooked by society.
Mr. Kelly was an expert on fingerprints. He was consulted on many criminal cases, leading to an invitation to join Vidocq, the society that works on cold cases.
He helped bring to the group's attention the famous case of "The Boy in the Box," or "America's Unknown Child," and spent nine years poring over old records, checking the boy's footprint against those of other city children. He had hoped to learn the child's name.
"Everyone deserves a name," he said of the case.
Blond, 4 to 6 years old, and wrapped in a plaid blanket, the boy was found in a cardboard box on a trash heap in Fox Chase on Feb. 25, 1957. Despite years of intense investigation, the case remains a mystery.
The boy was buried in the city's potter's field in Parkwood, in part due to Mr. Kelly's efforts, and then reburied in 1998 at Ivy Hill Cemetery in Mount Airy.
Mr. Kelly was determined that the child's story should be told and that the boy's life be honored with a yearly memorial service, his family said.
Mr. Kelly's own funeral and interment were private. Plans for a memorial service were pending.
Surviving are his wife of 62 years, Ruth Ann Buckley; sons William F. and Kevin B.; daughters Kathleen Greene and Eileen Rose Everitt; 10 grandchildren; six great-grandchildren; and a brother. A son, Michael, and daughter, Irene McKnight, died earlier.
Donations may be made to the Men of Malvern, 315 S. Warren Ave., Malvern, Pa. 19355, or the Sisters of Mary Immaculate, 118 Park Rd., Leechburg, Pa. 15656.