Ashley Tisdale Has Cutest Reaction to Learning BFF Austin Butler Is Her Cousin: 'Literally Am Going to Cry'

Ashley Tisdale and Austin Butler aren't just BFFs — the celebrity besties recently learned they're actually related!

The High School Musical actress, 37, found out about her family link to the Elvis star, 31, on the latest episode of Ancestry's 2 Lies & A Leaf series. It turns out that Tisdale and Butler — who both starred in 2009's Aliens in the Attic and 2011's Sharpay's Fabulous Adventure — are 10th cousins once removed.

"Austin and I always say that we're like fraternal twins born very far apart because he's much younger and we've always had that connection," the Frenshe founder told her sister, Jennifer, who was also featured in the episode.

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Tisdale was tasked with choosing between former castmates Butler, Zac Efron and Dylan and Cole Sprouse as her possible relative. Because of her closeness with Butler, she correctly chose him.

The two sisters then said with excitement, "Oh my God!"

"No wonder we have such a connection!" Tisdale continued. "We've always said we were brother and sister! That is insane. I literally am going to cry."

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Tisdale then referred to Butler as her "best, best friend."

"I'm telling you when we first met, I was like 'Oh, my God,'" she added. "We were like brother and sister from the minute we met."

At the end of the episode, Tisdale revealed that she texted Butler the news of their familial connection. Sharing the actor's response, Tisdale said: "He goes, 'No f---ing way.'"

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The longtime pals have forged a very close friendship since working on their two films together. Previously, Tisdale described Butler as her "twin born 7 years later" while celebrating his 30th birthday last year.

"You've been my closest friend through the years. You're the type of friend that came over when I was crying on the floor from a horrible breakup and not only lifted me off the ground but brought my favorite candy," she wrote in a tribute post. "I honestly didn't think anyone would ever understand me like you, but then enter my husband [Christopher French] and you happily embraced him like a brother. There's no one like you Austin."

Earlier this year, Tisdale and Butler reconnected face to face for the first time in two-and-half years.

"When you haven't seen your best friend in 2 1/2 years," she wrote alongside a photo of the pair in January. "You hold on real tight and don't wanna let go."