Dakota Fanning Celebrates Her 21st Birthday on Watch What Happens Live, Dishes on the Olsen Twins—Watch Now!

Former child star also answers Andy Cohen's question about "the oddest thing" Tom Cruise ever did on set of War of the Worlds

By Rebecca Macatee Feb 25, 2015 1:56 PMTags

Former child star Dakota Fanning is all grown up, and to celebrate her 21st birthday (and zero arrests to date!), she stopped by the Bravo clubhouse Tuesday for Watch What Happens Live!

Andy Cohen joked that he felt "bad" for "plying her with alcohol," but the newly legal-to-drink star seemed quite capable of handling her booze. Alongside Real Housewives of Beverly Hills personality Lisa Rinna, she played "Plead the Fifth" and "Never Have I Ever Whatsoever," and after the show, she even dished on her relationship with the Olsen twins and their little sister!

It started when a caller asked the Effie Gray star if she had to pick between Mary-Kate and Ashley Olsen, who would she want as her very best friend? "Here's the thing," Dakota began. "Their younger sister Lizzie [Elizabeth Olsen] is who I know the best. We went to the same high school, we have a lot of mutual friends and we did a film together [Very Good Girls]..."

After that deflection, Dakota got real. "I've only truly met them [Mary-Kate and Ashley] a couple of times," she admitted, "so I don't think I know them well enough to answer that question."

Womp, womp!

As for which twin has the better style? "From what I know," Dakota said, "they both have that."

She added, too, in agreement with Andy, "Both of them are totally lovely!"

Fair enough. But, did Dakota have any dirt to dish on Tom Cruise, her co-star in 2005's War of the Worlds? Watch the clip above to find out what she had to say about "the oddest thing" he ever did on set!

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