The former Saved By The Bell star went casual for the charity screening held on Sunday, 8 March.
Tiffani, 41, looked fab in her simple black dress and denim jacket for the event, which benefited the LA chapter of JDRF, an organisation which funds research into curing, treating and preventing type 1 diabetes.
The actress is expecting her second child with husband Brady Smith. They're already parents to daughter Harper Renn, born in 2010.
She's revealed baby number two is a boy.
During a recent appearance on The Tonight Show with Jimmy Fallon, the star revealed Harper couldn't wait to meet her little brother.
Tiffani said: "[She keeps saying], 'Is he ready? Is he ready?' Like he's a cake! The first name she came up with because she knew it was a boy was Spider-Man. It was a good name and I'm sure daddy would be okay with it but I think we'll name it something else!"
Probably for the best!
Tiffani also spoke about that recent Saved By The Bell reunion she did for The Tonight Show, saying: "I think all of us knew it would do well but I never in my life thought it would be like that!"
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