Heather Rae El Moussa's friendship with her husband's ex-wife is "developing"

And, she explained that working with Christina on 'The Flip Off' has led to them bonding.

She told Us Weekly: "I think friendship is a very special thing, like being a friend. And I think we're getting there, right? We're opening up to each other about things. We help each other through things. We talk about personal things with each other and guide each other through things. So our friendship is developing even more and more.

"It did [surprise me] because we talk about the kids. It's school, school stuff and homework and discipline and sports, but then, we don't know each other. We didn't know each other on a deeper level of who we are as individuals and filming a show together and being around each other more outside of just the children. ['The Flip Off'] got us to know each other on more of a friendship level."

Heather also revealed she would love to work with Christina again if 'The Flip Off' gets renewed for a second season.

She said: "It's an incredible show. We are very hands-on. We are ex ecutive producers. We helped create the show. We started in the show, and there's always trash talk with Tar and Christina, not so much me. I mean, it's fun to gang up on my husband. He's just easy and he has fun with it.

Christina and I, we've built a friendship throughout The Flip Off and we co-parent together and Mother's Day is coming up, which is exciting. We get to celebrate each other as mothers. But yeah, there's always a little trash talk. It's fun, but it's healthy."