Nicole Richie and Joel Madden made their 4-year romance official by tying the knot over the weekend in a private wedding ceremony at Nicole’s father Lionel Richie‘s estate in Beverly Hills.

The couple exchanged wedding vows in front of 150 guests, including Khloe Kardashian and mom Kris Jenner, Gwen Stefani and husband Gavin Rossdale, Samantha Ronson and more. Invited celebs who could not make the ceremony included Kim Kardashian and Christina Aguilera.

An insider says Joel’s twin brother and Good Charlotte bandmate Benji Madden was the best man, while Samantha Ronson served as Nicole’s maid of honor. And you’ll NEVER guess who officiated the star-studded wedding. Hit the link below to find out…

According to US Magazine, the wedding was officiated by Rev. Run, who doesn’t have “Reverend” in front of his name just because it looks good. Apparently, the Run DMC founding member (real name: Joseph Simmons) is an ordained minister!

“Joel and Nicole have looked up to Rev. Run, so they wanted him to officiate,” a guest of the wedding told UsMagazine.com exclusively. Explains the guest: “They both appreciate his family values and he is an inspiration for both. They both also respect his faith, too.”

Among the invited celebrity guests, friends and close relatives was a trained elephant.

But one attendee stood way out: a trained elephant was spotted being led into the Los Angeles estate of Richie’s father, music superstar Lionel Richie, where two tents were set up for the ceremony on a warm evening. How the elephant fit in wasn’t immediately known. (People)

Joel and Nicole’s 2-year-old daughter Harlow and their 15-month-old son Sparrow were also part of the celebration, serving as the flower girl and ring bearer.

Thoughts?