A bad mom as she was said to be, Britney Spears recently stunned mother-of-three Heidi Klum when she offered up her diaper-changing expertise.

The troubled singer showed up uninvited at Klum's annual Halloween party at Los Angeles venue Green Door, but the two quickly bonded over baby talk, media reports said Wednesday.

"We were talking about babies and diapers and she explained to me a lot of things about diapers I that didn't know," said the German supermodel.

Britney then went on to solve the diaper mystery that was perplexing Heidi.

"You know these sticky things on the side? I never knew that they were there. To close them in the front, I was always putting string around. I had no idea," said Klum.

"It's very clever. I learned a lot of things," she added.

(Agencies via Xinhua November 15, 2007)