By RUTH WALKER, U.S. BOOKS EDITOR Audrey Hepburn had more fame, glamour and adoration than she could ever have hoped for as a little girl, starving and terrified under the Nazi occupation of the Netherlands. But the iconic star of films including Roman Holiday – for which she won a Best Actress Oscar – My Fair Lady and Breakfast at Tiffany's would have given it all up in a heartbeat for her deepest desire: that of a large family and 'oodles of children.' Which makes a revelation in the latest, 'final word' biography of the beloved actress, written by her son Sean Hepburn Ferrer, all the more upsetting. In his book, Intimate Audrey,…