More than any other celebrity, Nicole Richie's style evolution has mirrored her own growth and transformation. From disheveled to polished, Goth to boho, the fashion designer has tried every look. Yet through marriage and motherhood she has finally found a middle ground that seems impossibly effortless.

Shortly after getting out of rehab for heroine and cocaine abuse, Richie starred in The Simple Life with her BFF Paris Hilton. She was considered Hilton's funny sidekick. Her hair was long and unstyled while her clothes, like her life at the time, were a mess. It was during the fifth season of the show that Richie got a DUI and was sentenced to four days in jail. During this time Richie was frequently photographed partying and looking disheveled.

Nicole Richie Nicole Richie, star of the Fox television network reality series "The Simple Life" and daughter of singer Lionel Richie, poses as she arrives at the 2003 Billboard Music Awards at the MGM Grand Garden Arena in Las Vegas, Nevada, December 10, 2003.

In 2005 Richie guest-starred in a series of television shows and released her first book The Truth About Diamonds. During this time she was already working with famed stylist Rachel Zoe and was starting to become known for her chic boho style. As she took on more adult responsibilities her style started to look more refined. She also appeared noticeably slimmer.

In 2006 Richie was frequently photographed in bikinis with the public and press expressing concern over her dramatic weight loss and bony frame. This was a year of getting rid of what Richie felt wasn't working in her life — her hair (she cut it short and shaggy) and ultimately her stylist, Rachel Zoe. Although the two are now friends again there were harsh words exchanged between them at the time despite the fact that many credit Zoe for transforming Richie into a trendsetter.

Nicole Richie Actress Nicole Richie arrives for the grand opening of Social Hollywood in Hollywood, California June 27, 2006. This event included a silent auction to benefit the Charlize Theron Africa Outreach Program.

Shortly after leaving Zoe, Richie met her now-husband Joel Madden. This marked an emotional and visual transformation for her. She created "The Richie Madden Children's Foundation," announced the launch of her accessories line House of Harlow and became pregnant with her daughter. She seemed to be more grounded and happier in her life and skin. This was reflected in her bold-yet-chic fashion choices that reflected a new, more polished, star.

During Richie's second pregnancy she dyed her hair dark, as many women do in order to avoid toxic chemical exposure to their unborn child. Often this shift opens the door to experiment with fashion. It appears a second pregnancy gave Richie added confidence in herself and her body, adding enough self-assurance to experiment with her look.

Nicole Richie Nicole Richie poses with her fiancee, musician Joel Madden, as they arrive at the 82nd Academy Awards in Hollywood, March 7, 2010.

Now a wife, mother of two, successful designer, and mentor on Fashion Star Richie seems to have found her stride in her looks and life. Nevertheless her rebellious spirit and spunky attitude constantly keep us guessing. Because, after all, she is Nicole Richie.

Nicole Richie Socialite Nicole Richie arrives at the Metropolitan Museum of Art Costume Institute Benefit celebrating the opening of "PUNK: Chaos to Couture" in New York, May 6, 2013.

Dr. Jenn Berman is a licensed therapist in private practice in Beverly Hills. She is the host of VH1 Couples Therapy and The Love and Sex Show with Dr. Jenn on Cosmo Radio on Sirius XM. She is the author of two best-selling parenting books and one children's book. Dr. Berman is the creator of the No More Diets app which is available for the iPhone and iPad. She also has an eco-friendly clothing line called Retail Therapy.