Well, that's exactly what KStew had to contend with when she filmed her latest movie Sils Maria.
She worked alongside French star Juliette Binoche, the same women who appeared in a very racy scene with Robert Pattinson in Cosmopolis.
However, if Kristen was feeling awkward about RPatz's time in the back of a limo with the older actress, she didn't show it on set.
The film's director Olivier Assayas has spoken at Cannes about the actress's relationship.
He said, "Kristen was very much a fan of Juliette.
She loves her work and she felt that she had something to learn from her, and I think Juliette loved that position of being able to pass on something to another actress.
Kristen watched her a lot and learned a lot from her and used it.
It was absolutely not competitive, it was something symbiotic," reports The Hollywood Reporter.
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