Kate Middleton asked a shocking question to Prince William on their wedding day, reveals an author.

The Prince and Princess of Wales, who tied the knot in Westminster Abbey in 2011, shared a cheeky conversation post wedding.

Royal author Robert Hardman writes in book ‘Catherine: The Princess of Wales: The Biography’ that Kate climbed turned to him and asked “are you happy?”

William then responded: “It was amazing. I’m so proud you’re my wife”.

This comes as Kate Middleton lauded her husband for his endless support during her cancer ordeal.

She touched upon “an incredibly tough couple of months for our entire family" in an emotional message, adding that “having William by my side is a great source of comfort and reassurance.”