Kate Middleton is in her final month of pregnancy and the question on everyone's mind is: Will it be a boy or a girl? According to The Telegraph, sources from inside St. James Palace are saying that the sex of the baby is a mystery, even to the Duke and Duchess of Cambridge, who have opted to wait to find out whether or not the next heir to the throne will be a Prince or Princess. We polled InStyle.com's readers back in March after People reported that Kate let slip that she’s having a girl, and the results were telling: 81% of voted for a girl, while only 19% voted for a boy. With the discussion heating back up as her due date approaches, we're looking to you again to get your thoughts. So, is Kate having a boy or a girl? Tell us by voting in the poll below!