“It’s very difficult,” Ann, 79, tells PEOPLE.
On Feb. 10, 1984, Kevin — the 7th of her 9 children — vanished while waiting for the bus in the Haight-Ashbury district of San Francisco after basketball practice at St. Agnes School.
The shy, freckle-faced boy was last seen talking to a tall man with a black dog at about 6:30 p.m., she says. Kevin didn’t get on the bus and never made it home.
“The time between November and February is the hardest,” says Ann, one of the family members featured on tonight’s episode of People Magazine Investigates on Investigation Discovery, airing Nov. 18 at 10 p.m. ET.
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Not only is that stretch filled with holidays that remind her of her missing son, but his birthday falls on Jan. 24 — 17 days before the anniversary of the day he disappeared.
“He was really just a sweet little boy,” she says.
Laura Collins, 55, the oldest of the Collins children, says her little brother’s disappearance still affects her.
“Depending on where you are in your life or what time of year it is, stuff that doesn’t ever bother you all of a sudden bothers you,” she says.
For years, the family had no idea what happened to Kevin, who became one of the first children to be featured on milk cartons across the nation.
Finally, in 2013, when the San Francisco Police Department’s cold case unit reopened the case, they learned investigators had pinpointed a viable suspect: a convicted pedophile named Wayne Jackson. A drifter who went by many names including Dan Therrien, Jackson lived down the street from the school and had a black dog, like the man with whom Kevin was last seen.
Jackson 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. Nothing has come of that in the past six years.
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Most of the time Ann feels like crying when she imagines what Kevin’s life would have been like had he not been snatched from the streets 35 years ago.
Other times she gets angry. “I think, how dare you take a child,” she says.
Kevin’s disappearance rocked the family. Ann and her husband, David, ended up divorcing. Two of their sons battle severe mental illness. The rest of the family suffered, too.
“The trauma of it was like being shipwrecked,” says Laura. “We lost everything and were on this raft together, just clinging to each other to live.”
One way the family coped with Kevin’s loss was by helping others. Shortly after Kevin vanished, Ann, David and her brother, Michael Deasy, set up the Kevin Collins Foundation for Missing Children, to help families facing the same nightmare.
The foundation closed shop in 1996, due to the strain of searching for missing children for 12 years. “We worked so many cases where children were found murdered,” says Laura. “They were horrific cases. It was so traumatic for all of us.”
The pain, she says, “never really ends. When someone you love dies, you’re supposed to own that grieving process. We were denied all of that.”
People Magazine Investigates: Vanished airs Monday, Nov. 11 at 10 p.m. on Investigation Discovery.