The former Spice Girls stars - who duetted on 'I Know Him So Well' last year - love singing even when they aren't working and are never afraid to grab a mic wherever they are.
Emma said: ''Mel and I perform ['I Know Him So Well'] wherever we can. Even if we go out to a cafe, we'll have a little singing. Mel and I did karaoke at her birthday last year.''
Emma is proud of the fact the Spice Girls' hits are available to sing in karaoke clubs all over the world as she knows not all artists enjoy such global success.
She said: ''I was with Mel C and Geri Halliwell the other day - we were making cheesecake - and we talked about that. We're very proud of the fact we worked hard and travelled the world. Not all bands can say that.''
Despite her love of singing, Emma - who has sons Beau, six, and Tate, two, with fiance Jade Jones - won't be returning to the recording studio any time soon.
She told OK! magazine: ''I do love music and I would really like to do it again, but at the moment I can't take that time away from the children. But who knows.''
The novel's author saw a cut of the film and loved each of the changes the movie's director had made.