What was the worst gift Prince William gave Kate Middleton during their engagement?

What was the worst gift Prince William gave Kate Middleton during their engagement? 

Prince William revealed the worst gift he gave his wife, Kate Middleton, during their engagement, during a podcast with Peter Crouch on BBC Radio, and said he made a disappointing joke that Kate still reminds him of.

He gave her an endoscope, and said, “Everything went wrong. To be honest, I have no idea why I bought the speculum, so it seemed like a good idea.”

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