The 45-year-old played deranged witch Bellatrix LeStrange in the film series, and started work on the sixth movie in the franchise just 12 weeks after welcoming her daughter Nell, reported Sun online.
"I really couldn't jump up and down and scream without losing most of my bodily liquid. They had these air dryers (on set), these huge things - that's where I would dry myself off.
"None of the men (knew I wore diapers). They don't know, you see. But all the girls were, like, 'How can you?' But, actually, I don't think I was too embarrassed. There's something quite liberating about having a baby... I loved having a baby. I would have a baby every day if (I could). The birth day is fantastic. It is magic. It is complete magic," she said. PTI NDS