Watch: Nicole Richie Reveals How She Set Up Cameron Diaz and Benji Madden

Could Nicole Richie and Cameron Diaz wind up as sisters-in-law? Nicole Richie made an appearance on Watch What Happens Live last night, alongside Rachel Maddow, to promote her show Candidly Nicole, and she opened up about the adorable couple, Cameron and Benji Madden.

OK! News: Eva Mendes is seven months pregnant! Get the details.

Benji is the twin brother of Nicole's husband Joel Madden, and rumor had it that she set up the lovebirds. "I approve of anything that's going to make Benj happy," the newly blue-haired reality star said coyly to a viewer's question about going on a double date with the pair. "I am a devoted sister-in-law, and I am happy for anyone that's happy.

OK! News: Jenelle Evans just issued the best insult to someone who insulted her second baby.

"I'm going to take responsibility for everything," Nicole joked when Andy Cohen asked if she set Cameron and Benji up. Her fellow guest Rachel called her out on the lie, but let's just appreciate the fact that Nicole cosigned their coupledom! Camji is totally happening. Maybe less so on the nickname...

PHOTOS: A few reasons why Rihanna is the ultimate sports fan.

What do you think of Cameron Diaz and Benji Madden together? Do you think they make a cute couple? Do they have a future? Tell us in the comments below or tweet us @OKMagazine.