The actress shared a funny post on Instagram

Jennifer Garner took a trip down memory lane this week. The actress marked the 20th anniversary of one of her very first films, , and joked that the milestone had left her a little confused!

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Jennifer starred in the movie alongside Ashton Kutcher, Seann William Scott and Marla Sokoloff, who played her twin sister. Taking to Instagram at the weekend, the star shared a photo of the two ladies together, writing: "This week, #DudeWheresMyCar turned twenty (Dude!) and my beautiful friend @marlasokoliff, who played my twin, turned 40 (sweet!). Holy cow, does that mean I'm 40, too?"

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Marla was quick to respond to the post, quipping: "Awwwww, thank you twin! I'm just so confused… weren't we just at your 30th?!"

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Jennifer shared her funny post on Instagram

There is in fact eight years between Marla and Jennifer, who celebrated her 48th birthday in April. Not that she looks it – the beautiful actress is often lauded for her incredibly youthful appearance, and in a previous interview she shared the secrets of her skincare routine.

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"Looks weren't a big deal in my family," she told . "I don't think my parents ever said 'you're pretty' and so we just didn't think about it."

The star shares three children with ex-husband Ben Affleck

However, Jennifer revealed she started to notice sun damage as she got older. "We would put on baby oil and lay in the sun to try to get brown," she confessed. "When I was a young girl, my sisters spent most of the time on a boat. We would just burn and then peel it off and then burn again and peel it off."

To help combat this damage, the star said the first thing she does in the morning is put on sunscreen. "Keep sunscreen everywhere, and always apply more than you think you need," she confided. "You just have to be a nerd about it, and get it done!"

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