This is an I-Heart podcast.

Guaranteed Human.

For years, Richard Petrone lived in the apartment above his parents' bakery.

By 2005, Richard had moved out and was living in an apartment in South Philly to be closer to his daughter.

On the day after he went missing, his mother, Marge, wondered if she'd find any clues in his apartment.

I said I should go up there.

I saw his laundry and his, you know, refrigerator full,

and I saw concert tickets for like March on his desk.

Everything was like he was coming back.

As she worked her way through her son's apartment,

she couldn't reconcile all the evidence of her son's everyday life

and the reality of his profound absence.

He had some Christmas gadgets and stuff that he didn't even take apart and fix yet.

And I thought, what am I looking at?

It was just left like you would leave and you were coming back.

It was one of the worst days of my life.

Across town, Danielle's mother, Felice,

held out hope her daughter would return.

My mother, she was always optimistic.

She had a two-bedroom condo and one bedroom,

she had the bed made with like a gift on the pillow for my sister.

It was just heartbreaking.

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