EXCLUSIVE: Callie Is Thrown for a Loop When a Stranger Drops a Bombshell on 'The Fosters' Summer Finale

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Talk about a twist!

All season on The Fosters, Callie (Maia Mitchell) has been advocating for a new trial for her former foster brother, Kyle, who was convicted of murdering a woman -- a crime she believes he couldn’t have committed. It’s been a serious endeavor for Callie, who continues to track down leads and campaign for Kyle’s release.

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As the Freeform drama wraps up its summer run, Callie is about to get thrown for a loop. In ET’s exclusive sneak peek from Monday’s summer finale, a stranger approaches her Justice for Jack booth at the bayside festival she’s stationed at.

Expecting a warm reception from the young man, Callie is taken aback when she receives some resistance after asking him to donate to Kyle’s defense fund.

“No, I won’t,” he says plainly. “You shouldn’t be doing that. You’re raising money for a murderer.”

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“Well, he isn’t a murderer,” Callie replies matter-of-factly. But the young man isn’t budging. Why? Turns out, he’s the victim’s grandson.

Things are about to get interesting!

The Fosters
wraps its summer run Monday at 8 p.m. ET/PT on Freeform.