The event, which took place at Soho House in West Hollywood, was featured with a "Star Wars" themed cake with a message, "May the force be with baby Newman", reported Aceshowbiz.
According to a photo which was shared by "Revenge" star Ashley Madekwe, the cake was shaped like a planet and detailed with characters from the George Lucas movies as well as clothespins and pacifiers.
There was also a replica of King as Princess Lea and her husband of six years Kyle Newman on the cake. Actresses Selma Blair, Jessica Alba, Jared Eng and Claudia Lee attended the bash.
Teresa Palmer, who is expecting her first child, and her fiance Mark Webber were also among the guests, along with King's "Hart of Dixie" co-stars Rachel Bilson and Wilson Bethel.
King and Newman, who met on the set of "Fanboys", tied the knot in 2007 after two years of dating. The actress-model announced in May that she was expecting her first child with Newman.
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