Fergie spent her birthday on Sunday helping to raise money for the Japanese relief effort by joining her actor husband Josh Duhamel for his star-studded charity run in California.
The Transformers star organised the Tokidoki Youth Relief Run along Santa Monica beach after seeing the devastation caused by the 9.0-magnitude earthquake and tsunami which hit the country earlier this month.
All runners were asked to pay $10 to enter the event and Duhamel called on people of all ages to take part in the two-mile sprint to boost donations for the American Red Cross' Japan Earthquake and Pacific Tsunami fund.
Celebrities including Glee actress Dianna Agron, socialite Paris Hilton, her designer sister Nicky and the Black Eyed Peas star all showed their support for the charity drive by donning their running shoes for the race.
Taking to Twitter.com after the run, Duhamel wrote, "We did it! 4,000+ people pack the beach! The youth of LA mobilized & should be proud. All of u that donated should be proud. Much love..JD."
Details about exactly how much cash was raised from the Relief Run were unavailable as WENN went to press.
Duhamel organized a similar run to raise funds for Haiti following the earthquake in the country last year.
Meanwhile, Fergie and Duhamel celebrated the pop star's 36th birthday early by partying at The Bank Nightclub in Las Vegas on Friday. The singer was treated to a rendition of Happy Birthday by clubgoers before jumping on the microphone and performing a verse from her band's hit song "Imma Be."
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