Mike Tindall was forced to admit "I don't know what to say" when he was grilled about the Royal Family live on Good Morning Britain.
The rugby star appeared on the show alongside former teammate James Haskell to promote their new book 'The Good, the Bad and the Rugby - Unleashed', which follows on from their podcast by the same name, co-hosted with Alex Payne.
But Mike, who married Zara Tindall in 2011, was thrown off when the conversation turned to his relationship with his royal mother-in-law, Princess Anne.
Presenter Susanna Reid asked: "What do you call Princess Anne?" Mike sheepishly revealed that when it comes to addressing Princess Anne, he opts for: "Ma'am.
Read more on dailyrecord.co.uk