Nicole Richie  turns 32 today! To celebrate the big day, we're taking a look back at Nicole's pretty radical transformation over the years, from her days of partying with Paris Hilton  and Lindsay Lohan  to her current status as a wife, mother, and all-around style star. While there may have been some bumps in the road throughout her career, it's safe to say that Nicole has come out on top. Not only is she devoted to her adorable family, but she's also a bona fide businesswoman juggling multiple fashion lines, children's charities, and stints on shows like Project Runway and Fashion Star. In honor of Nicole's big day, click through to see her epic metamorphosis over the years.
Nicole Richie  showed off her patriotic side in a slinky American flag print top at a Las Vegas club opening in November 2001.
Nicole Richie  attended a benefit party in LA in her then-signature brand of brights in March 2002.
Whoa, girl! Nicole Richie  bared (almost) all in a sheer tiger-print dress that didn't leave much to the imagination. It was actually pretty appropriate for the occasion — a Frederick's of Hollywood party in April 2002.
Nicole Richie  and Paris Hilton  partied in skimpy ensembles at a Hollywood bash in June 2002.
Before they headed to a rural farm town for the first season of The Simple Life, Fox threw Nicole Richie  and Paris Hilton  a bon voyage bash that was attended by their celeb pals, including a mohawk-wearing Kelly Osbourne, in April 2003.
Nicole Richie  hit up a pre-Emmys party in September 2003 and posed for photos with some cast members from Queer Eye For the Straight Guy (remember that show?).
Nicole Richie  and an almost-unrecognizable Taryn Manning attended a Halloween  party together in October 2003.
Nicole Richie  and Paris Hilton  showed up in monochromatic looks for The Simple Life premiere party in December 2003.
Nicole Richie  and Paris Hilton  hit the stage together to present at the Billboard Music Awards in December 2003.
Nicole Richie  and Paris Hilton  hung out in the gifting suite during the Sundance Film Festival in January 2004 — check out that ancient flip phone!
Nicole Richie  was anything but mellow in this head-to-toe yellow look at a GM event in Hollywood back in February 2004.
Nicole Richie  and Paris Hilton  were two of a (colorful) kind at their Simple Life welcome home party in April 2004.
Nicole Richie  rocked a color-coordinated look for a PlayStation 2 bash in LA in May 2004.
Nicole Richie  went for a mature suited-up look while attending a Fox event with her mom, Brenda, in June 2004.
Nicole Richie  hit the red carpet for her Teen Choice Awards hosting gig alongside Paris Hilton  in August 2004.
Nicole Richie  was given a sweet smooch by her then-boyfriend, the late DJ AM, as they sat front row for the Monique Lhuillier  runway show in September 2004.
Nicole Richie  and Paris Hilton  showed up together for Mariah Carey 's annual Halloween  party in NYC back in October 2004.
Nicole Richie  showed off a rather stunning red carpet look for the Billboard Music Awards in December 2004.
Nicole Richie  and Christina Aguilera  showed off their shiny new engagement rings — courtesy of DJ AM and Jordan Bratman, respectively — at a Roberto Cavalli  store opening in LA in February 2005.
A slimmed-down Nicole Richie  showed up in style for a Marc Jacobs  boutique opening in LA back in March 2005.
How's this for a blast from the past? Nicole Richie  and a blond Lindsay Lohan  stepped out together for a Cartier  bash in May 2005.
Nicole Richie  — with a cute new blond bob — signed autographs of her first book, The Truth About Diamonds, at an LA Barnes and Noble store in November 2005.
Nicole Richie  and her then-stylist Rachel Zoe  attended the Marchesa  runway show together during New York Fashion Week in February 2006.
Nicole Richie  and DJ AM (who was then her fiancé) packed on the PDA during his surprise birthday party in Las Vegas in April 2006.
Nicole Richie  was surprised with a birthday cake of her own during a Teen Vogue Young Hollywood party in LA in September 2006.
Nicole Richie  was the belle of the ball at a launch party for the T-Mobile Sidekick in October 2006 (yes, we said T-Mobile Sidekick).
Nicole Richie  joined Rachel Zoe  at a cocktail party for designer Charlotte Ronson  in LA back in October 2006.
A dark-haired Nicole Richie  stuck close to her pal Paris Hilton  during an LA soirée in November 2006.
Nicole Richie  flashed a peace sign at a Disney Couture party hosted by her longtime friend Kidada Jones in May 2007.
In December 2007, Nicole Richie  showed off her growing baby bump while launching The Richie Madden Children's Foundation with Joel Madden , who was then just her boyfriend.
Nicole Richie  and Joel Madden  launched another children's charity initiative together in September 2008.
Look at little Harlow! Nicole Richie  and Joel Madden  brought their baby girl to the Kidstock Music and Art Festival in LA in May 2009.
Just a year after giving birth to Harlow Madden, Nicole Richie  put her second baby bump on display at an event in LA in August 2009, this time expecting her son, Sparrow.
Joel Madden  and Nicole Richie  had a sweet date night at a Knicks game in NYC back in February 2010.
Nicole Richie  and Joel Madden  kicked the glamour up a notch for the Oscars red carpet in March 2010.
Nicole Richie  signed copies of her second book, Priceless, at an LA Barnes and Noble store in October 2010.
Nicole Richie  and Joel Madden  brought their kids, Harlow and Sparrow, to a Yo Gabba Gabba! concert in LA in November 2010.
Nicole Richie  went for a vintage look when she and Joel attended Elton John's annual Oscars viewing party in February 2011.
Nicole Richie  and Joel Madden  spent a fun family day with their little ones, Harlow and Sparrow, at a Disney event in London during October 2011.
Nicole Richie  joined her Fashion Star cohorts, Elle Macpherson and John Varvatos , at the show's premiere party in NYC in March 2012.
Nicole Richie  joined her dad, Lionel, on stage during his special Las Vegas concert in April 2012 — so sweet!
Nicole Richie  launched her House of Harlow  collection at Sydney's David Jones store in May 2012.
Nicole Richie  attended a launch event for her fragrance, Nicole, at Macy's in LA in August 2012.
Further cementing her style star status, Nicole Richie  was honored at the Style Awards in NYC in September 2012.
Nicole Richie  and Joel Madden  made the most of their night out during an LA Macy's event in September 2012.
Nicole Richie  expanded her empire with a special line for Macy's Impulse, and feted the launch in NYC in September 2012.
Nicole Richie  turned it out on the red carpet at the ALMA Awards in LA in September 2012.
Nicole Richie  went for a '20s-inspired look when she attended the Baby2Baby Gala with Jessica Alba  in November 2012.
Nicole Richie  got a sweet smooch from her son, Sparrow Madden, during a birthday party in July 2012.
Nicole Richie  was a vision in blue when she walked the red carpet at the Golden Globes in LA in January 2013.
Nicole Richie  shared a cute moment with her godfather, Quincy Jones, during a pre-Grammys gala in LA in February 2013.
After launching a clothing line for QVC, Nicole Richie  hit the red carpet for the company's big LA bash in February 2013.
Nicole Richie  and her husband, Joel Madden , were on hand for Elton John's annual Oscars viewing party in LA in February 2013.
How chic did Nicole Richie  look on the arm of Elle creative director Joe Zee? The duo arrived for the Stella McCartney  show during Paris Fashion Week together in March 2013.
Nicole Richie  spoke on stage during AOL's Digital Content NewFronts while promoting her online show, Candidly Nicole, in April 2013.
Nicole Richie  debuted a high-fashion look for the punk-themed Met Gala in NYC in May 2013.
Nicole Richie  glammed it up for the CFDA Fashion Awards in NYC in June 2013.
Nicole Richie  broke it down with Mario Lopez during a July 2013 appearance on Extra in LA.
Nicole Richie  took a stroll with her daughter, Harlow Madden, in LA in July 2013.
Nicole Richie  joined her husband, Joel Madden , and their kids, Harlow and Sparrow, for a walk to the beach during their July 2013 vacation in St.-Tropez.
Nicole Richie  sported a sequin Giorgio Armani  jumpsuit while hosting the Style Awards in NYC in September 2013.
Nicole Richie  stepped out for a Nordstrom  store opening party in LA in September 2013.