The former England rugby star — who has been married to King Charles’ niece Zara Tindall since 2011 — was asked how he addresses the Princess Royal in private and admitted itwas not any different to the way other people speak to her in public.
When asked by host Susanna Reid on Good Morning Britain on Monday what he calls his mother-in-law, Tindall responded: “Ma’am.”
Last year, Tindall and his The Good, The Bad and The Rugby podcast co-hosts Alex Payne and James Haskell secured a joint interview with Anne, Prince William, and Catherine, Princess of Wales in their capacities as patrons of Scottish, Welsh and English rugby respectively.
And the former I’m A Celebrity... Get Me Out Of Here! contestant praised his in-laws for being “amazing” guests.
Mike Tindall has been married to Princess Anne's daughter Zara since 2011. Photo / Getty Images
“Rugby has been going through a tough time and we wanted to showcase why it brings people together from all backgrounds. It’s such an inclusive sport, but it also creates great human beings.
“It was more important to showcase why they like sport, why Princess Anne has been a patron of [the Scottish Rugby Union] for 37 years and why she loves the characters in the game.
“It accepts all fans and they come from all sides.”
Tindall previously shared that the royal family does not live like Downton Abbey.
He opened up on his experiences with the royals, and how late monarch Queen Elizabeth II enjoyed a more “normal” life, despite people expecting it to be like a scene from Julian Fellowes’ period drama.
In his new book The Good, the Bad and the Rugby - Unleashed — which he co-wrote with James and Alex — he said: “I’m sometimes asked if the Queen did informality like ‘normal’ people, and the answer to that is yes.
“Her life wasn’t like an episode of Downton Abbey, with meals on long tables and everyone dressed in their finery every night.”
