David Walliams thinks Simon Cowell needs to get used to changing nappies.

The comedian has advised his fellow 'Britain's Got Talent' judge to get some hands-on experience of the less glamorous aspects of parenthood after he becomes a dad for the first time, joking he'll need the practice for when he has to look after 'X Factor' judge Louis Walsh in years to come.

Speaking on UK TV chat show 'Lorraine', David said: ''It's one of those things, so many men say, 'I'm never going to change a nappy', it's actually not that bad. It's part of loving your child. And one day, he's going to have to change Louis Walsh's nappies - so he'd better get used to it now!''

The funnyman scoffed at Simon's statement he won't be in the delivery room with his girlfriend Lauren Silverman when the baby - who he hinted was going to be a boy - is born.

David - who has a four-month-old son Alfred with his model wife Lara Stone - exclaimed: ''Of course you want to be there at the birth, it's a completely magical event. To hear your baby cry for the first time...''

The 42-year-old star also shed some light on Simon's diva-like behaviour on the 'BGT' set, claiming his entourage give everyone minute-by-minute accounts of his exact whereabouts.

He scoffed: ''He has that kind of persona where he kind of likes to wind us all up. He likes the attention, as long as he's the centre of attention he's happy.

''He's always really late, he sometimes arrives at 4 o'clock in the afternoon. We get bulletins. Simon's five minutes away, Simon's one minute away. Simon's walking up the stairs. Simon's about to come in the door!''