Most fans know that when Sasha Pieterse began playing Alison on 'Pretty Little Liars,' she was super young. In fact, she was the youngest cast member, even if viewers couldn't tell by watching her act.

She's grown up a lot over the years, but Sasha's always been supremely mature, which is how she landed her role on 'PLL' with no trouble at all. She was originally in the running to play Hanna, noted CheatSheet, but when the truth came out about her age, they changed their minds.

As for why Sasha lied in the first place, there's a simple answer for that.

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Hollywood wouldn't have wanted to cast a 12-year-old in a role meant for someone in their early 20s. After all, most "teens" in film are way older than they look.

Sasha Pieterse impressed producers with her acting chops, of course, and they were considering her for the role of Hanna. Cosmopolitan even highlighted a rumor that said Sasha didn't reveal her true age until after she'd filmed the pilot of 'PLL.' If that's true, it's "very Alison of her," says the publication.

Regardless, Pieterse's acting was what earned her a job, but she couldn't tackle the full-time role of Hanna for two reasons: one, producers were uncomfortable with her doing typical teen stuff at the tender age of 12. Two: they couldn't have her work many hours since she was under 16.

Although, Sasha did graduate at the age of 14, so it wasn't like she was still in high school during every season. Plus, she had a few roles before her big debut on 'PLL,' so it sort of seems like producers should have realized her age from the get-go. She'd already starred in a project alongside Buffy, after all (in 2007's 'The Air I Breathe')!

Though Pieterse did turn 13 early on in the show's timeline, she was still the baby of the cast, even if she didn't act that way. And she cherished her time on the show as well as the opportunity to add more depth to her character throughout the seasons. Though at first, she worried about how fans would perceive the character, noted CheatSheet.

She needn't have worried; audiences loved her interpretation of Alison, and she became a fan favorite.

She's since said goodbye to her character, at least partly. Sasha Pieterse is a mama now, and she's now at the ripe old age of 24 if fans can believe it.

The real question is, will Sasha and the rest of the cast appear on the reboot of 'Pretty Little Liars'? Fans have their fingers crossed, but for now, it's a waiting game.

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