Article continues below advertisementOK! can reveal former royal butler Paul Burrell has lifted the lid on what he has branded Andrew Mountbatten-Windsor and Sarah Ferguson's disgusting early-marriage habit - as shamed ex-duke Andrew faces fresh humiliation following his arrest in the Jeffrey Epstein investigation.Burrell, 67, an ex-manservant who tended to Queen Elizabeth II and later became a confidant of Princess Diana's, makes the revelation in his memoir The Royal Insider: My Life with the Queen, the King and Princess.