The late Queen Elizabeth II made her only daughter the Princess Royal in June 1987, but did you know that Princess Anne's royal title is very rare?
The Princess, who turns 73 next month, is only the seventh person to have held the title of Princess Royal since its establishment by Charles I for his daughter, Princess Mary, in 1642.
While the title is traditionally bestowed upon the eldest daughter of the sovereign, it is not automatic. The last Princess Royal before Anne was Princess Mary, the only daughter of King George V and Queen Mary, who died in 1965.
The title remained vacant for 22 years before the Queen bestowed it upon Princess Anne on 13 June 1987.
The title is held for life, even if the holder outlives her parent the monarch, which is why King George VI was unable to create his eldest daughter, Princess Elizabeth, the Princess Royal, because her aunt, Princess Mary, was in possession of the title at the time.
Similarly, if Princess Anne is still using the title when her nephew, Prince William, ascends the throne, he will not be able to bestow it upon his daughter, Princess Charlotte.
Princess Anne married her first husband, Captain Mark Phillips, in 1973 and the pair share two children, Zara Tindall and Peter Phillips.
The couple separated in 1989 and finalised their divorce three years later. Anne went on to wed Vice Admiral Sir Timothy Laurence in 1992 and the couple reside at the Princess' Gloucester home, Gatcombe Park.
Anne is grandmother to Peter and his former wife Autumn's daughters, Savannah, 12, and Isla, 11, as well as Zara and Mike Tindall's three children, Mia, nine, Lena, five, and two-year-old Lucas.
Captain Mark Phillips is not a member of the royal family, and he declined the offer of an earldom, so Peter and Zara were not given titles from birth.
Peter is currently head of partner acquisition for the sports and entertainment rights agency CSM Sport & Entertainment, while Zara is an equestrian and won a silver medal as part of Team GB's Eventing team at the London 2012 Olympics.