I really need some clarification over whether Prince William, Kate Middleton and Prince Harry would be considered muggles. I somehow doubt the royal trio got any clarification on this while visiting the new Making of Harry Potter studio tour. Sure, they received all the attention, but can they make some levitate and fight off mystical creatures? Doubtful.
Just look at Kate here. It's like she's trying so hard to channel her magical powers with this faux-Harry Potter wand. Too bad the royal baby couldn't lend a helping hand here.