By Brad Edwards

CHICAGO (CBS) — More than 60 years have passed since two young Chicago sisters went to see an Elvis Presley movie and never returned home.

2 Investigator Brad Edwards recently caught up with some people who haven’t lost hope that the killer will be found.

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The bodies of Barbara and Patricia Grimes were discovered Jan. 22, 1957 in what is now Burr Ridge.

The sisters had been missing since the night of Dec. 28, 1956. They had left home to see the Presley feature “Love Me Tender” at the Brighton Theater. They never returned.

Patricia was 13; Barbara was 15. Their killer or killers were never caught, but the Cook County Sheriff’s Office is still working the cold case.

Detective Jason Moran acknowledges the challenge he faces.

“Sometimes the passage of time works against you,” he says.

Former Chicago police investigator Raymond Johnson is an expert on the case. He says he believes confessed child killer Charles Melquist did it. Melquist, who is deceased, was never charged in the deaths of the Grimes sisters.

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Edwards followed up on a lead suggested by Johnson. There is an elderly man, still living, who knows “the most of what happened,” he says.

The man – CBS 2 is not naming him – talked with reporter Edwards on the phone but declined to talk about the murders.

“It’s all in the past,” he said. “That’s all I can say.”

Edwards also spoke with the girls’ brother, Jim Grimes, 72, who has never done an interview. He was 11 when his sisters were killed.

“They were supposed to come home right after the show,” he says.

The surviving sibling says he’s haunted by many questions about what happened.

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“There’s just so much that you think about. There’s just no answers,” Grimes says.

Brad Edwards