The Olsens: Celebrating 22 years Photo by: Everett Collection; Richard Young / Startraks
Mary-Kate and Ashley Turn 22 – at Bonnaroo! | Ashley Olsen, Mary-Kate Olsen
It may be Friday the 13th, but it's a happy day for Mary-Kate Olsen and Ashley Olsen: They celebrate their 22nd birthday today.

Yes, it's been more than 21 years since the twins first became stars – the California natives began sharing the role of Michelle Tanner on Full House before their first birthday.

According to local news reports, the Olsens have been spotted in Nashville on their way to the Bonnaroo music festival in Manchester, Tenn. The lineup for the four-day festival includes performances by Kanye West, Metallica and Willie Nelson.

It'll be a far cry from their last birthday: The multimillionaire moguls hosted a quiet family dinner party at Hollywood's Chateau Marmont that included their sister Lizzie, 20, and brother Trent, 24.

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