Sarah Ferguson is said to be preparing a dramatic return to the public stage with a tell-all memoir – a move source tell OK! has triggered unprecedented legal planning within the royal household as King Charles and Prince William consider ways to prevent the publication of explosive claims about the monarchy. Ferguson, 66, the former Duchess of York, has spent recent months largely outside the United Kingdom amid mounting controversy surrounding her former husband Andrew Mountbatten-Windsor, 66, who is currently under investigation on suspicion of misconduct in public office. Andrew has not been charged with any crime and denies wrongdoing....