By Joe Holden

PHILADELPHIA (CBS) — A Philadelphia man gunned down in his own home. Shelton Hayes had just returned from celebrating his birthday. Three years later, his murder remains unsolved.

Even as investigators say they have exhausted all leads, Hayes’s mother has vowed to never give up.

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It was a loud noise that broke the silence.

“I said, ‘Why are you making so much noise this early in the morning?’ And the voice that I heard replied, ‘I’m good, mom. I hit the TV, don’t come down,'” Rhone Gore said.

Hayes had been out the night of March 14 celebrating his birthday. It was 4:30 a.m. and the father of two had already checked on his mother.

“He came upstairs, he went to the restroom, and always checks on me,” Gore said, “and that’s the last time I saw my son alive.”

Hayes had been shot once in the back of the head. His lifeless body lay on the floor inside the home he shared with his mother in the 7700 block of Overbrook Road in Overbrook Park.

Gore says she never heard a gunshot — just that loud bang. She discovered her son facedown on the floor after she came downstairs to leave for work. She frantically called 911. She remembers praying.

Police and news crews were now milling about outside.

She vividly recalled going back and forth with officers.

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“I said, ‘What do you mean I can’t go anywhere?’ She said, ‘Mam, you can’t leave?’ ‘Why can’t I leave? I need to go to the hospital, and I need to see about my child, see what’s going on, is he all right, what’s going on?’ And she said you can’t go anywhere until homicide detectives talk to you,” Gore recalled. “And I said what do you mean homicide detectives need to speak to me? Are you telling me my child is dead? She stopped talking. It’s been three long years since that terrible night in March of 2018.”

Even the sign recalling his memory is starting to fade. What’s not fading is a mother’s resolve. She wants his killer to hear these words.

“Let me tell you personally, I forgive you,” Gore said. “I don’t care about the why. I care about the what.”

This grieving mother says her heart breaks for the family of her son’s killer when justice is eventually served.

“The big difference is, they are going to be able to go to prison and see you,” Gore said. “I have to look on top of my china closet to see my son.”

Philadelphia Police tell CBS3 Mysteries they’ve exhausted leads. No person of interest was ever developed, and they have no motive beyond speculating.

This mom is desperate to know who killed a man known to be the life of the party.

“He was a good man,” Gore said. “He is a good man.”

She prays for answers and for justice.

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If you have any information that could help Gore and detectives, please reach out to the Philadelphia Police Department at 215-686-8477.