Jessica Simpson is nervous about returning to reality TV.
The singer and designer had her own show 'Newlyweds' with former husband Nick Lachey, which ran for three seasons until 2005, but she has decided to make a return to the medium to appear on her sister Ashlee's new E! docuseries 'Ashlee+Evan' with husband Evan Ross.
Jessica told E! News: "I mean, being on reality TV definitely makes me hyperventilate a little bit. I'm not one for being mic'd up all day. I stick my foot in my mouth too much!
"I'm on their show, definitely, a for a big moment. But really, the show is about their discovery in their music and in their relationship. It's very exciting. They're so cute together. I'm exciting for the world to see what I've already seen."
Ashlee and Evan, 29, recently announced that they were allowing the cameras into their home for their new show, which will document them as they work on an album together.
Ashlee said: "We decided to make this album out of love and kind of going back to duets when that was a thing."
The couple have daughter Jagger, two, together, and the 33-year-old singer also has son Bronx, nine, with ex-husband Pete Wentz.
Both children will make brief appearances on the new show.
Although Jessica's first marriage to Nick Lachey broke down soon after filming ended on their reality TV show, Evan isn't worried that the docuseries will affect his relationship with Ashlee.
He said recently: "I think in any relationship in this industry, there's a stress on relationships. I think that's reality, but in no way do I think that if a relationship is meant to be together and a marriage is meant to be together, that anything like a show or being in this industry can change that."