The star, whose birthday is April 19, began celebrating on Friday night with the company of some of the biggest stars in showbiz, according to People.
Kate's "How To Lose A Guy In 10 Days," and "Fool's Gold" co-star, Matthew McConaughey, as well as pals Tobey Maguire, Justin Timberlake, Gwen Stefani, Evan Mendes, Adam Sandler, Zach Braff and Cher all reportedly made the event, which was held at the Pacific Palisades home of Kate's mom, Goldie Hawn, and her partner, Kurt Russell. Also in attendance were celeb couples Demi Moore and Ashton Kutcher, Jessica Alba and Cash Warren, and Gwyneth Paltrow and Chris Martin,
"Kate was elated, dancing all night, having the time of her life – and she looked amazing in a very sexy little dress and [Christian] Louboutin heels," a source told the mag. "She gave a very touching speech and spoke about how important her family is to her."
The source added that it was showman Justin who got the party going.
"Justin Timberlake was the life of the party," the source said. "He was dancing, drinking tequila, and he had everyone doing the 'electric slide' on the dance floor."
However, the party may have been too out of hand for some – according to X-17 Online, police arrived on the property late Friday night in response to a noise complaint.
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