Celebrity Zac Efron, Ashley Tisdale Party on the Beach The High School Musical costars celebrate Tisdale's birthday beachside on Saturday By Alison Schwartz Published on July 3, 2011 11:45 AM Share Tweet Pin Email Photo: GSI Media What did Zac Efron get longtime pal Ashley Tisdale for her 26th birthday? A beachside piggyback ride! The shirtless hunk, 23, was spotted giving his High School Musical costar a friendly lift as they marked the VnC Cocktails and Heineken Light-sponsored milestone Saturday in Malibu, Calif. “So happy zacary made it to my party!” Tisdale, who sported a striped Mara Hoffman bikini, Tweeted. “He’s my brother/best friend!” Red, White & Woo! How Stars Celebrated the 4th After frolicking in the sand – with buff and bronzed bods on display – Efron gave the birthday girl an encore piggyback ride as they headed back to a nearby friend’s home to continue the festivities.