The High School Musical star, 36, posted a series of Instagram Stories on Thursday in which she shares a sweet hug with Butler, 30.
She wrote on her Instagram Story, "When you haven't seen your best friend in 2 1/2 years," and added on her second Story, "You hold on real tight and don't wanna let go."
The pair have known each other since they were 15 years old and costarred in Disney Channel's Sharpay's Fabulous Adventure in 2011.
The get-together was not the first time that Tisdale has shared her bond with the actor with her social media followers. On his 30th birthday last August, Tisdale posted a heartfelt tribute to Butler and called him her "twin born 7 years later."
"You've been my best friend since you were 15 so that's 15 years strong of friendship," she wrote. "I am beyond proud of you and everything you're accomplishing but most importantly proud of the person you are."
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"You've been my closest friend through the years," Tisdale added. "I honestly didn't think anyone would ever understand me like you but then enter my husband and You happily embraced him like a brother."
Tisdale shares daughter Jupiter Iris, 9 months, with her husband Christopher French.