Nicole Richie says that fiancé Joel Madden is a hands-on dad to their daughter – particularly when it comes to changing diapers.

The new mom reveals that baby Harlow is the centre of her life but she’s happy to let the Good Charlotte rocker get his hands dirty.

"Joel actually changes more diapers than I do," she tells Extra in an interview airing tonight.

"It's his time with her. He sings to her...He laughs with her, plays with her. It's amazing."

Despite sadling her man with diaper duty, Nicole says she’s loving motherhood.

"Everything I do is for her," she says. "I was so excited from the minute I found out I was pregnant...and it's been nothing but an amazing ride since."

Check out Nicole's post-baby bod here.