See why Zac Efron Goes Shirtless on Valentine’s Day

Zac Efron posted a shirtless photo while reading to his three-year-old sister, Olivia.

Source: Instagram

In this photo Zac is reading for little sister Olivia

Source: Instagram

The photo shows Zac's toned abs while Olivia snuggles up next to him holding a stuffed animal.

Source: Instagram

Zac's brother, Dylan, commented on the post claiming Olivia as his own valentine.

Source: Instagram

Zac frequently posts adorable photos with his little sister, including a recent slideshow for her birthday.

Source: Instagram

Zac often posts photos of himself working out or shirtless.

Source: Instagram

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