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What a gentleman: For her 25th birthday, Nick Lachey stepped back and let wife Jessica Simpson have the dance floor. "I felt it wasn't the right moment to show her up," he says jokingly. "I was being a gracious husband."
Hipster deejay Charlotte Ronson spun for Simpson and her 150 guests at the Encino, Calif., bash on July 9. Ronson kicked things off with Simpson's version of "These Boots Are Made for Walking" from the Dukes of Hazzard soundtrack. And when she threw on Beyonce's "Crazy in Love," the guest of honor showed off her best moves alongside pals Eva Mendes and CaCee Cobb.
"Turning 25 was an amazing experience for me," Simpson tells us. "Having my family and friends there made it even more special." Celebs including Jake Gyllenhaal, Mandy Moore, Topher Grace and Joaquin Phoenix joined her for the party (held the night before her actual b-day). "It was great to see everyone come out and support Jessica on a very special day for her," says Lachey.
Dad Joe Simpson even got a little emotional. "Looking around our yard and seeing all the people who love my daughter was, at times, overwhelming," he says.
After reveling for almost six hours, the party wrapped up well past 3 a.m. And guests didn't leave empty-handed: They walked away with gift bags by Silver Spoon including Poko Pano Brazilian bikinis, Theory clothing and Victoria's Secret sweatsuits.
"Being with my sister on her 25th birthday was such a blessing," says sib Ashlee Simpson. "The party was great!"