Fergie Celebrates 40th Birthday With Glamorous, Intimate Party: Details, Pic

Josh Duhamel and Fergie
Josh Duhamel toasted his wife Fergie at her 40th birthday party on March 21.  Amanda Edwards/WireImage

G-L-A-M-O-R-O-U-S, yeah! Fergie rang in her 40th birthday the only way she knows how — in style. The "L.A. Love" singer gathered up around 100 of her closest friends and family to celebrate her milestone birthday at her home in L.A.'s Brentwood neighborhood on Saturday, March 21. 

The intimate bash had an Old Hollywood theme and the guests all came in costume. An insider tells Us Weekly that the birthday girl wore a white silk one-shoulder gown with her hair down and wavy. 

The festivities mostly took place outside by the singer's pool that was decorated with white lights and a giant red light installation. DJ Richie Rich played for most of the night, featuring tracks from Maroon 5 to Sublime to the Black Eyed Peas themselves. 

Ferg's only bandmate to attend was apl.de.ap as the others were all in London at the time of the fete, according to a source. Kelly Osbourne was one of the few celebrity guests, and the lavender-haired Fashion Police escapee, 30, shared a photo from the event on Instagram, writing, "Just had the best night celebrating @fergie's #Birthday she is my #SisterFromAnotherMr!!!! true friendship is hard to find in this town!"

An insider tells Us that Fergie's husband of six years Josh Duhamel made a touching toast, "thanking her for being so amazing and having a boy for them too."

The mom of 18-month-old Axl enjoyed the company of her closest family, including her dad, John Patrick Ferguson, with whom she shares wine company Ferguson. Naturally, Ferguson wine was served as was a tasty berry cream cake from Sweet Lady Jane Bakery. 

"Her 40th seemed perfect," the insider revealed.

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