Britons are placing their bets on the gender and the name of Prince Harry and his wife, Meghan's, first child. Despite the royal couple keeping plans about their impending baby under wraps. If Britain's bookmakers are to be believed, it's definitely a girl. The William Hill agency closed the betting on the baby's gender a few days ago after an "avalanche" of bets poured in from people convinced the royal couple is having a girl. So far, Diana is topping the bookmakers' list as a front-running name. Firm spokesman Rupert Adams says he personally doubts Harry would choose a name that so directly evokes his iconic mother's tragic death in 1997. But Adams added that there's every chance of it being a middle name. Victoria, Alice, Grace and Elizabeth are close behind, while Albert, Arthur and James are popular guesses for a boy. Carolyn Harris, a royal historian who teaches at the University of Toronto's School of Continuing Studies, agrees that Diana could be a middle name. That's what Harry's brother, Prince William, and his wife Kate did for their daughter, Princess Charlotte -- the three-year-old's full name is Charlotte Elizabeth Diana. Harris believes a possible middle name could be Ruth — after one of Meghan's great-grandmothers, as well as Diana's maternal grandmother, Lady Ruth Fermoy. Harry and Meghan haven't announced the baby's gender or the due date, which is widely believed to be sometime in late April.