Baby's first ... rave?!
Holly Madison attended the Electric Daisy Carnival (A.K.A. EDC) over the weekend in Las Vegas -- and while her newborn daughter Rainbow didn't actually go with her, her famous mama did dress her up for the occasion.
After teasing that the little girl would be "behind the scenes with me and her daddy [EDC founder Pasquale Rotella] all weekend," Madison posed in a number of costumes with the baby ... who looked pretty terrified by the whole ordeal.
Not convinced? Check out this additional photo below:
"I wanted to get her some colorful festival wear just for fun," added Holly ... who dressed as a bee and an extra from Katy Perry's "California Gurls" music video.
Confused face aside, Rainbow is one adorable little girl. Check out more celeb kids in the gallery above!