Celeb mums join friend for fiesta

Nicole Richie and Jessica Alba, both 31, left their little ones at home to spend the night partying with Kirsten Dunst, 30, and Rachel Zoe, 41, in LA.

The mums-of-two headed out together to celebrate friend and fashion writer Derek Blasberg‘s 31st birthday.

Nicole showed off her tiny figure in monochrome
stripes whereas Kristen and Jess kept things casual in floral prints.

Derek uploaded a picture of the night to his Instagram.

Happy birthday to ME! With a bevy birthday babes: Kiki, Kelly, Nicole, Jess, Rachel and Lauren,‘ he wrote.

Happy Barfday @derekblasberg! I had a blast at your #Fiesta last night,’ Jess posted.

Jess and Nicole have only recently returned from a holiday together in St Barths where they went late-night snorkelling with mates.

On the boat at midnight about to get our snorkel on… Terrified,’ Jess posted.

Love vacay w the homes!

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