Zara Tindall, who celebrated her 44th birthday tomorrow, doesn't hold a royal title for a very simple reason. Her mother Anne, the Princess Royal, just didn't want her children to have any offical titles. The King's sister wanted her children - Zara and Peter Phillips - to, despite being members of the Royal Family, lead normal lives.

Althought there are specific rules for who can hold a princess and prince title, the late Queen Elizabeth II was reportedly prepared to bend the rules for her daughter's children. Originally the rule, which dates from Letters Patent by King George V in 1917, said that all the children of the sovereign, the male-line grandchildren and the Prince of Wales’s eldest son were all allowed to hold a princely style.

This means that traditionally Zara wouldn't have been allowed to be known as a princess - something that her cousins Princesses Beatrice and Eugenie hold.

In 2012, the year before the Prince and Princess of Wales welcomed Prince George into the world, the late Queen - who died in 2022 - issued a new Letters Patent, which changed the Law of Succession to absolute primogeniture.

The new rule meant that all three of the Prince and Princess of Wales's children were titled as princes or princesses - and Prince Louis - born in 2018 - was not allowed to overtake Princess Charlotte - born in 2015 - in the line of succession.

Despite not being granted a princess title at birth, Zara, who turns 44 on May 15, has previously said that she is pleased with her mother's decision.

She previously said: "I’m very lucky that both my parents decided to not use the title and we grew up and did all the things that gave us the opportunity to do."

Although not titled as prince and princess, Zara's two other cousins - Lady Louise Windsor, 21, and 17-year-old James, Earl of Wessex - hold different royal titles.

When their parents, Prince Edward and Duchess Sophie, become the Duke and Duchess of Edinburgh in 2022, many fans wondered whether their children would then take on the prince and princess titles. Speaking to The Sunday Times in 2020, Sophie said: "We try to bring them up with the understanding that they are very likely to have to work for a living. Hence we made the decision not to use HRH titles. They have them and can decide to use them from 18, but it’s highly unlikely."

Like their mum, all three of Zara's children - Mia, 11, Lena, 6, and four-year-old Lucas - do not have royal titles.