Princess Anne's son Peter Phillips reveals warning he would get before balcony appearances

The Princess Royal's children Peter Phillips and Zara Tindall joke about being on their best behaviour during Buckingham Palace balcony appearances in a new documentary to celebrate their mother's 70th birthday.

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Speaking on ITV's Anne: The Princess Royal at 70, Zara says: "For me and like… family occasions were all about hanging out with our cousins and just having as much fun as possible."

Her older brother Peter then adds: "You then get a clip round the ear and say right, behave yourself, you know, we’re going out on the balcony. Don't pick your nose and you know, don't yawn."

William (in front of the Queen) with Zara (L), Peter and Harry on the balcony in 1986

The siblings would often appear on the palace's famous balcony with their cousins Prince William and Prince Harry when they were growing up. Peter, 42, and Zara, 39, are the Queen's oldest grandchildren, but Princess Anne and their father Captain Mark Phillips decided not to give their children royal titles when they were born.

Peter says in the documentary: "We were always brought up on the understanding that we were gonna have to go to work. We were gonna have to go out and earn our, earn our living. Regardless of the fact of who our grandmother was or who are mother was."

Zara adds: "I think it made us fight harder as well, to try and be as successful as we could be. Erm, so I definitely, you know I’m very, we're very grateful to her not giving us a title anyway [laughs]."

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Princess Anne, who has spoken about the decision for her children previously, says: "As a member of the royal family, living with that sort of pressure is, is hard and the expectations that come with it is hard. And that might have been at the bottom of the list, that it may be less difficult for you. But actually, understanding where they sit within the family and what happens next, it made much more sense."

Zara, who is an accomplished equestrian and won a silver medal in Team Eventing at the London 2012 Olympics, is also a director at Cheltenham racecourse. Meanwhile, Peter has worked for Jaguar as a corporate hospitality manager and then for the Williams racing team. He also had a role as a manager for RBS, before leaving in 2012 to become a managing director at sports and entertainment agency, SEL UK.

Anne: The Princess Royal airs on 29 July at 9pm on ITV

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