The Sin City star voices villain Lena Thackleman, a scheming big-headed blue alien, in the animated adventure and she was excited to show her eldest child the finished product.
She tells the New York Daily News, ""Rarely do I get an opportunity to make a move that my kids can see. When it comes to me doing movies, she'll come on the set and pretty much think I sit in a trailer and get different hair and make-up done. She has no idea. So it's nice to show her this is what I do.""
However, Alba didn't quite expect the reaction she received: ""She did ask me, though, after she saw it, 'Mummy, was it hot when you wore that mask?' Was it hot? I was like, 'Oh, my God, she doesn't know the difference between live action and animation!'""
Alba isn't the only celebrity in the movie - Brendan Fraser, Ricky Gervais, Sofia Vergara, Sarah Jessica Parker and Jane Lynch also lend their vocal talents to characters in the film.