The former Kate Middleton's use of one letter has the British press speculating that Catherine may have given away the sex of her baby.
According to Britain's Telegraph newspaper, the letter Catherine used was "d."
"Thank you, I'll take that for my d ..." Catherine said, per the paper, after a member of the public handed her a teddy bear on Tuesday.
Another person - Sandra Cook, who was standing next to the woman who gave Catherine the toy - then chimed in.
"I said to her: 'You were going to say daughter weren't you?' and she said 'No, we don't know,'" the woman told the paper. "I said 'Oh I think you do,' to which she said: 'We're not telling.'"
Prince William and Catherine are expected to welcome their first child in July.
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