Nearly 18 years later, everyone remains hopeful they'll learn what happened to LeeAnna Warner — including the police
leeana warner

At about 5 p.m. on a Saturday, the day before Father's Day in 2003, LeeAnna Warner, her sister Karlee and their mother returned to their suburban Chisholm, Minn., home after a day of shopping and swimming.

LeeAnna told her mom Kaelin that she wanted to walk around the corner to say good night to her best friend. "It was a normal thing," Kaelin recalls.

But the day turned out to be anything but normal.

Kaelin sent older sister Karlee to bring her home. "She said, 'Mommy, I can't find her,' " Kaelin says.

For more on this case and others, subscribe now to PEOPLE or pick up this week's issue, on newsstands Friday, and tune in to learn about the case of missing LeeAnna Warner in Little Girl Gone on People Magazine Investigates, airing May 3, 10 p.m. ET on Investigation Discovery and streaming on discovery+.

When Kaelin went to look herself, she found LeeAnna's shoes outside the friend's house, where no one had been at home for LeeAnna's visit.

"That was the last time I saw her," Kaelin says nearly 18 years later of the moment that turned her and her husband Chris Warner's lives upside-down.

In 2020 alone, there were some 365,348 reports of missing kids, according to the FBI. John Bischoff, vice president of the Missing Children Division at the nonprofit National Center for Missing & Exploited Children says there is "always the hope" of finding them no matter how long they've been missing.

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Vernon Manner, chief of Chisholm Police, who had been with the police department for eight years when LeeAnna disappeared, agrees.

"Somebody knows something," he says. "We're still hopeful."

Anyone with information about the case should call the Chisholm Police Department at 218-254-7915.