Nicole Richie Hangs Out with Cameron Diaz and Mariah Carey Before Her Father's Concert

Nicole Richie is not having your typical Monday. In fact, it's pretty darn fabulous. The House of Harlow designer posted a photo on Instagram of her and a large group of friends backstage before her father Lionel Richie's concert tonight, and there are more than a few famous faces in the shot.

In the 'gram, we spot Richie's sister-in-law, Cameron Diaz, Lake Bell, and jewelry designer Jennifer Meyer in the photo, but there's one person in the crowd that will make you do a double-take—Mariah Carey! You can see her posing front and center in a dazzling sequined dress. If you're thinking that this is the most random group of celebrities ever, it kind of is, but that just makes it even more amazing. "Happy Monday my lambs #touchmybody," Richie captioned the photo.

While the assortment of famous people definitely feels random, Carey is currently doing a few shows on Richie's All the Hits tour, which is going on now, so it does make sense that Nicole and her pals would snag a picture with the pop star.

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Regardless of how it came to be, all in all it's pretty epic.