Demi's bottom Twitter post

Ashton Kutcher posted a picture of Demi Moore's bottom on his Twitter page

There must be many advantages to marrying a man 15 years younger than yourself, but dealing with his schoolboy sense of humour probably isn't one of them.

Demi Moore discovered to her cost yesterday that husband Ashton Kutcher's love of practical jokes does not end at their front door.

Ashton, 31, posted a picture of Demi's bottom - clad only in small white knickers - on his Twitter page yesterday.

All he wrote was, 'Shhh, don't tell wifey.'

The pair were in the Caribbean for the wedding of Demi's ex Bruce Willis to his new wife Emma Heming.

Earlier in the day Ashton had Twittered that he was watching his wife steam his suit wearing nothing but a bikini.

Luckily Demi, 46, saw the funny side of his secret Tweets. She posted back, 'He is such a sneak and while I was steaming his suit too!'

The Punk'd host is famous for playing practical jokes on celebrities and filming them for his TV series.

We're sure living with him must be a laugh a minute, eh Demi?

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