Madonna'S former nanny is set to pen a sensational memoir sharing behind-the-scenes information about the pop icon and her family. MELISSA DUMAS, who worked for the LIKE A VIRGIN singer throughout 2005 and 2006, has handed an 80-page book proposal to publishers for evaluation, according to a US entertainment site. The book, which is said to be brokering a $5 million (GBP2.6 million) deal, will expose intimate details of Madonna's marriage to SNATCH director Guy Ritchie, the behaviour of children LOURDES and ROCCO and the story leading up to the adoption of Malawian baby DAVID BANDA. Dumas did not sign a confidentiality agreement when she began working for Madonna. Though she is said to have been handed a gagging order when she quit, she has not signed it.