As Prince Edward and Sophie Rhys-Jones look forward to their marriage on June 19, a potentially explosive unofficial biography of Edward threatens to cast a controversial cloud over the proceedings, revealed Britain’s Express. American-based British writer Wendy Leigh’s book, “Edward Windsor,” promises to look into many of the scandalous rumors that have surrounded Edward. and it will be published in America only — not in the UK, where libel laws are considered more stringent than they are in America. (Leigh is the author who was locked in a libel suit with Arnold Schwarzenegger for the bio she wrote about him and his father’s alleged Nazi past.) “Without going into details, the book is certainly likely to cause a stir,” a literary source told the Express. “Leigh’s technique is very much no-holds-barred.” It is likely to delve into such touchy subjects as rumors about Edward’s homosexuality, his controversial quitting of the Royal Marines and his troubled relationship with his father.”