Zac Efron Posts Adorable Birthday Tribute to His 'Lil Sis' Olivia

Zac Efron is melting hearts with his super sweet sibling post, wishing his baby sister Olivia a happy birthday on social media.

The actor, 35, took to Instagram on Monday to share a tribute to the darling little girl.

"Happy bday lil sis," Efron captioned the adorable set of photos, adding a princess emoji. The three-year-old wore a crocheted flower crown on her head, while the chiseled star sported a mustache.

In the first photo, Efron was captured smiling sweetly at the girl, who looked up in admiration at her older brother. The second photo shows the tan, California native lovingly smooching the top of Olivia's head as she closes her eyes and rests her head on his chest.

"IM CRYING STOP😭," one of the actor's 56.7 million fans commented on his dad vibes. "She looks like she needs an auntie," quipped another admirer, assuming the little girl was his niece.

A third follower was a bit more direct, expressing: "Can you pls be the father of my children."

Efron back

Efron previously posted about his sister in 2021, sharing a photo of him holding her with the caption: "My sister Olivia, little heartbreaker."

Before reuniting with his family for the holidays, the actor was seen last month on the New Orleans set of his upcoming wrestling movie The Iron Claw. Efron was still wearing the same costume he was photographed in on set earlier in the month when he and costar Lily James were spotted filming scenes for the upcoming A24 film.

Efron wore a grey tank top, cutoff jean shorts, white Nike sneakers and white socks, complete with a bowl cut Monday for his portrayal of former pro wrestler Kevin Von Erich.

Efron, who most recently appeared in the movie The Greatest Beer Run Ever, has been sporting his muscly physique on the set of the upcoming movie for over a month.

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The High School Musical alum recently admitted that he felt underprepared to play a dad in his 2022 horror film Firestarter.

"You know what? I think that was a healthy dose to put me off of it for as long as necessary," he told Ellen DeGeneres in May of his role as a "full-on" father in the 2022 adaptation of Stephen King's book. "I have a bit more growing to do, probably. I don't know. Yeah, I don't know what to say now."

Though he added: "I have a healthy respect for parents, very grateful for them all. I love you so much mom."