Nicole Richie turns 31 today! It's been an eventful year for her. In the last month alone, Nicole launched her Macy's line, hit up a star-studded wedding in Cabo San Lucas, and debuted her first fragrance. A busy schedule hasn't prevented Nicole from running with a fabulous group of friends, though. Over the years, she's kept the company of friends like Jessica Alba, Jennifer Lopez, and the Kardashians. Click through to see them all — and happy birthday Nicole!
Fox threw a bash in the Summer of 2003 to promote
Nicole Richie and Paris Hilton's show The Simple Life as well as Jason Bateman's Arrested Development.
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Naomi Campbell crossed paths with Nicole Richie in NYC during a September 2005 Fashion Week event.
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Nicole Richie met up backstage with Fergie at the December 2003 Billboard Music Awards in Las Vegas.
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Carmen Electra joined Nicole Richie at a May 2004 Art of Elysium event in Beverly Hills.
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Mariah Carey joked around with Nicole Richie at a 2004 Halloween party in NYC.
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Kelly Osbourne and
Nicole Richie cozied up for a photo at a party celebrating Teen People's Young Hollywood issue in August 2004.
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Diddy shared a hug with Nicole Richie during a September 2006 NYC Fashion Week charity event.
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Nicole Richie and Christina Aguilera showed off their engagement rings during a February 2005 bash at Roberto Cavalli's Beverly Hills store.
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Wilmer Valderrama stepped out to cheer on Nicole Richie at her June 2009 House of Harlow fashion show in Hollywood.
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Rachel Zoe joined her pal Nicole Richie at a shopping event at LA's The Grove in July 2005.
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Nicole Richie stopped to chat with Sophia Bush backstage at the 13th annual Race to Erase MS in May 2006.
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Nicole Richie chatted with Rachel Bilson during a dinner held at LA's Sunset Tower in July 2006.
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Marc Anthony and Jennifer Lopez met up with Nicole Richie and Joel Madden at L.A. Reid's post-Grammy dinner hosted by Jay-Z in January 2010.
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Nicole Richie hung out with Ashley Greene during Ella Moss's LA 10-year anniversary celebration in July 2011.
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Nicole Richie and Gwen Stefani posed for a photo during NYC's September 2005 Fashion Week.
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Jay-Z and Nicole Richie were on hand for Marc Jacobs's September 2008 runway show in NYC.
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Mary-Kate Olsen and Nicole Richie were both among the well-dressed stars at Proenza Schouler's September 2008 New York Fashion Week show.
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Nicole Richie smiled for a photo next to Alicia Keys at Zac Posen's February 2009 New York Fashion Week presentation.
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Lauren Conrad chatted with Nicole Richie during a UNICEF TAP Project fundraiser benefiting the Richie-Madden Children's Foundation in March 2009.
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Nicole in Da House
Pete Wentz was on hand in June 2009 for Nicole's House of Harlow 1960 fashion show in LA.
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Nicole Richie gave Maroon 5's Adam Levine a fist bump during a December 2009 Lakers game.
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Nicole Richie and Hayden Panettiere attended Elton John's Oscars party in March 2012.
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Kirsten Dunst met up with Nicole Richie in Beverly Hills at Art of Elysium's third annual black tie charity gala in January 2010.
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Nicole Richie and Paris Hilton shared a hug at an LA party celebrating The Simple Life 2 in April 2004.
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Nicole Richie joked around with Margherita Missoni and Kate Bosworth at Derek Blasberg's Beverly Hills book launch party in May 2010.
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Rose McGowan posed side by side with
Nicole Richie at the October 2010 CFDA Vogue Fashion Fund finalists celebration in LA.
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Nicole Richie snapped a photo with Jessica Simpson at the 2003 Billboard Music Awards in Las Vegas.
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Nicole Richie was escorted by Kanye West out of Jean Paul Gaultier's show in Paris in March 2011.
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Nicole Richie and actress Emma Roberts stepped out to support Ashley Olsen and her line TEXTILE Elizabeth and James during an April 2011 viewing of the collection in Beverly Hills.
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Nicole Richie was joined by her pal Jessica Alba at a West Hollywood Baby2Baby event in April 2011.
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Nicole Richie and Lucy Hale attended the Dior Beauty Garden Party held at LA's Chateau Marmont in October 2011.
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Nicole Richie, Amber Heard, and Jenna Dewan-Tatum met up at Elle's 18th Annual Women in Hollywood Tribute held at Beverly Hill's Four Seasons Hotel in October 2011.
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Nicole Richie celebrated Lindsay Lohan's birthday in West Hollywood in October 2011.
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Nicole Richie and Sharon Stone chatted at Macy's Glamorama event with Terry Chairman in LA in September.
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Nicole Richie and Michelle Monaghan got together at the 40th annual FiFi Awards in May.
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Nicole Richie, John Varvatos, and Elle Macpherson celebrated Fashion Star in NYC in March.
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Nicole Richie and Andy Cohen hit the Bravo red carpet before kicking off season six of Watch What Happens Live in March.
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Nicole Richie and Rashida Jones attended a pre-Grammys event in LA in February.
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Nicole Richie and Joy Bryant goofed off at the NBC TCAs party in LA in January.
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Nicole Richie showed support for Mindy Kaling in Hollywood at a toast for Mindy Kaling's book in November 2011.
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Nicole Richie and Jessica Simpson stopped by the Fashion Star studios to visit finalist Nzimiro Oputa in August 2011.
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Nicole Richie and Katharine McPhee linked up at the Golden Globes in January.
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Nicole Richie and Kourtney Kardashian posed together during the T-Mobile Sidekick 3 Launch Party at The Paladium in Hollywood in June 2006.
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Nicole Richie and Joel Madden attended the launch of The Richie Madden Children's Foundation in LA in December 2007.
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