Ashley Tisdale's daughter thought her 'High School Musical' co-star Zac Efron was her father.

The 39-year-old actress portrayed Sharpay Evans in the Disney Channel hit alongside Zac's Troy Bolton and when her three-year-old daughter Jupiter's actual dad, Christopher French, showed his little girl the 2006 musical movie, "about a year ago", she asked if the 37-year-old actor was her pop.

Speaking on the 'Breaking Beauty Podcast', Ashley recalled: "She thought Zac Efron was her dad.

"I was like, 'No, that's not daddy. Just cause they [both] have dark hair, it's not daddy.'"

Ashley - who also has four-month-old Emerson with her spouse - explained that her daughter is starting to establish that her mom is famous, but she doesn't quite understand acting yet.

The former 'The Suite Life of Zack and Cody' star added: "She did start to get to the age where she's questioning why people take pictures with me. And I truly did not know how to answer that.

"I just said, 'I don't know.' I think she actually thinks you just take pictures with people."

Meanwhile, another Hollywood star has a sweet bond with Jupiter.

'Elvis' star Austin Butler, 33, has been friends with Ashley since they were young and loves being a "fun uncle" figure.

Speaking at the premiere for his recent movie 'Bikeriders', he shared: "I play with the toys and whatnot, and then I can go home at the end of the day."

Praising Ashley's parenting, he added: "I feel so honoured to be a part of her life and to get to know her children."

Ashley and Austin met after they starred in the 2009 animation 'Aliens in the Attic' and also shared the screen in 2011' romantic-comedy 'Sharpay's Fabulous Adventure'.

Austin also used to date Ashley's 'High School Musical' co-star Vanessa Hudgens, 36.