Zac Efron & Ashley Tisdale - LEAD
Credit: Gregg DeGuire/WireImage

Troy + Sharpay = friends forever.

Zac Efron celebrated his 29th birthday yesterday, and longtime pal and High School Musical co-star Ashley Tisdale did not miss the opportunity to wish him well on social media.

Tisdale marked Efron's special day by sharing an adorable throwback photo of them from the film's set on Twitter, which she captioned: "Happy birthday buddy! @ZacEfron you will always be the Troy to my Sharpay. ❤️ you brother!" Several hours later, Efron replied to his friend with an equally heartwarming message, and wrote: "@ashleytisdale And you'll ALWAYS be my Ashley. Thanks luv





But what makes this lovefest even better? Earlier this month, Efron reunited with two of his other co-stars from the Disney flick, Lucas Grabeel and Corbin Bleu, and the handsome actor took to Instagram to share a snap from the nostalgia-inducing occasion. The Wildcat boys joined forces at the Broadway show Holiday Inn Musical, where Efron and Grabeel were on hand to support Bleu, who stars in the production.

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This just further confirms our feelings that a fourth installment of High School Musical starring the original cast needs to be made.