The shy fourth-grader waited for the bus on a busy San Francisco corner after basketball practice on a cold February night – and was never seen again

What Happened to 10-Year-Old Kevin Collins, Who Vanished from a Bus Stop in 1984?

Growing up in San Francisco, Kevin Collins was just like any other energetic little boy when he was around his 8 brothers and sisters and his cousins.

When his aunt, Jackie Deasy, 74, would stop by, “Kevin was just one of the kids that was flying all over the house,” she recalls.

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Even so, Kevin, 10, who battled dyslexia, “was quieter than most of the kids,” she says.

The family’s life changed forever on Feb. 10, 1984, when Kevin found himself alone after basketball practice (his 11-year-old brother, Gary, had stayed home sick). Rather than catch a ride home with the coach and kids from Gary’s team, the shy boy slipped out of the building to wait on the corner for the city bus. Witnesses saw him talking to a man with a black dog while he waited at the bus stop.

Kevin never made it home.

Image zoom Kevin Collins, 10, of San Francisco, who has been missing since 1984 National Center for Missing and Exploited Children

His mother, Ann Deasy Collins, instinctively knew something was wrong.

“I was petrified,” says Ann, now 79, who is among the family members featured in Monday’s episode of People Magazine Investigates on Investigation Discovery, airing Nov. 18 at 10 p.m. ET. “You know your kids.”

With Ann calling everyone she could think of, her twin brother, Michael Deasy, and her then-husband, David, scoured the neighborhood for any sign of the sweet, gap-toothed boy.

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They called police, who said Kevin could be at a friend’s house, Jackie recalls.

“We kept saying, ‘That’s not the case. Kevin wouldn’t go to a friend’s on his own,’” says Jackie. “I don’t think any of us really thought about stranger abduction at the time.”

With the authorities offering little help, the family took action, dividing up the city to search for Kevin, plastering fliers of his picture everywhere and manning a hotline round the clock, for months.

Even when Kevin became one of the first missing children to be featured on milk cartons nationwide — and was on the cover of Newsweek — he was not found.

In 2013, when the San Francisco Police Department’s cold case unit reopened the case, they told the family they believed they’d found a “viable” suspect: Wayne Jackson, a convicted pedophile who lived down the street from the school, who police had questioned in 1984, says Kevin’s sister, Michelle Collins, 52.

Image zoom Wayne Jackson San Francisco Police Department

Like the tall man with a black dog Kevin was seen talking to at the bus stop at 6:30 p.m. the night he vanished, Jackson had a black dog, says Michelle.

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He died in 2008, but since 2013, authorities have been trying to offer Jackson’s partner — who lives in Canada — immunity to tell them what he knows. So far, their attempts have been futile.

The family just wants to find out what happened to Kevin, or at least where his remains are. “We know it’s not going to be good,” Michelle says, “but we would like some answers.”

Kevin would be 45 years old today.

San Francisco Police had no comment, saying the case is “still open.” The District Attorney did not immediately return PEOPLE’s request for comment.

Anyone with information about Kevin’s case should call the San Francisco Police Department at (415) 553-0123.