Kira is the subject of the world's most expensive child support case. Las Vegas billionaire Kirk Kerkorian, 84, insists he is not Kira's father, because he is sterile, and he is challenging Miss Bonder's claim for £220,000 a month maintenance. Last month, Bing sued Kerkorian for £3.4 billion for invasion of privacy and trespass, claiming the octogenarian had organised for dental floss from his dustbin to be used to find a DNA sample.