Get ready for another British princess.

Kate Middleton seems to have let it slip that she's expecting a baby girl. She dropped the hint during a visit to the National Fishing Heritage Centre in Grimsby, England Tuesday. The pregnant Duchess of Cambridge was given a white teddy bear by a local. "Thank you, I'll take that for my d--" Prince William's wife replied, tellingly cutting herself off mid-sentence.

When someone asked her if she was about to say "daughter," Kate smiled and replied, "We're not telling."

A source says the royal couple recently learned the sex of their baby, "but they've only told their parents."

If it is a girl, it could be historic. The proposed Succession to the Crown Bill would overrule centuries of royal gender discrimination by decreeing that William and Kate's firstborn will be the heir to the throne regardless of its sex.

SOURCE: Us Magazine

PICS: Kate's Baby Bump