India, March 21 -- Kate Middleton allegedly treats her husband, Prince William, like her "fourth child," according to Tom Quinn. In his new book, Yes Ma'am: The Secret Life of Royal Servants, the author details his findings about the personal lives of the members of the royal family, which he learned after interviewing hundreds of former and current palace staffers.

"Occasionally, William has little tantrums and irritations if things aren't done the way he wants them done [as heir to the British throne]," Quinn told Fox News on Friday. The royal author claimed that the Princess of Wales is "very good at managing" Prince William the same way she parents their three children.

The Prince of Wales and Kate share Prince George, 11, Princess ...