Harlow’s Star-Studded Birthday Bash

Though the birthday girl herself, Harlow Winter Kate Madden, managed to slip by the photographers without getting her picture snapped, the guest list for her third birthday party read like a who's who of Hollywood! Harlow's mom and dad -- Nicole Richie and Joel Madden -- invited a host of celebs and their kids to help their daughter celebrate her big day at the Tree House Social Club in Beverly Hills on Saturday.

Among those on the star-studded list were Harlow's 16-month-old little brother Sparrow, "Grey's Anatomy" star Ellen Pompeo, her husband Chris Ivery, and their 15-month-old daughter Stella Luna (who looked seriously cool in oversized shades and a beanie), Kourtney Kardashian and her son Mason Dash Disick, 1, Gwen Stefani, Gavin Rossdale, and their sons Kingston, 4, and Zuma, 2, and Jessica Alba, Cash Warren, and their 2-year-old daughter Honor.

The Tree House Social Club has become quite the hot spot for Hollywood mommies, as the venue offers everything from spa treatments for moms to a giant play center for kids. People.com reports that Harlow had a few of her school friends attend in addition to the celeb crew, and the kids played outside in the tree house as well as enjoying arts and crafts projects inside.

Harlow -- whose actual birthday is Tuesday, January 11 -- blew out the candles on a specially crafted Sleeping Beauty-themed castle-shaped cake, and the lucky lady also got to hang out with Buzz Lightyear from "Toy Story" and Ariel from "The Little Mermaid." "Nicole and Joel chose those characters," the manager of the Tree House told E! Online.

Sounds like fun to me!

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