By Olivia Bahou
Updated: Jun 07, 2016 @ 2:02 pm
Donato Sardella/Getty

This famous family just keeps getting sweeter! Nicole Richie’s newest collection launch became a family affair last week when hubby Joel Madden, his brother Benji, and his bride Cameron Diaz showed up to support her new line. But the love affair isn’t over yet: Diaz just posted the sweetest message to her sister-in-law on Instagram.

In the photo, the famous pals are embracing at the party celebrating Richie’s House of Harlow 1960 collection with Revolve. “We’re sisters because of our misters and I am SO impressed by and proud of how talented she is,” the actress captioned the post. “Her capsule collection at Revolve is a wonderful reflection of her spirit and her style; sexy and chic, playful and grounded, feminine with a hint of masculine, retro yet contemporary. Congrats,” she wrote.

Richie told InStyle that the L.A.-inspired collection, which launched June 2 on, is inspired by her stylish friend group, herself included. “What do I see my friends wearing? What can we pair with other pieces that already exist in our closet? What is the summer vibe?” she asked herself when creating the line.

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