The Earl and Countess of Wessex's daughter, Lady Louise Windsor, celebrated her 18th birthday on Monday 8 November.
Born in 2003 at Frimley Park Hospital, she is the Queen's youngest granddaughter and is currently 16th in the line of succession.
READ: 18 best photos of Lady Louise Windsor to celebrate her milestone birthday
WATCH: The Earl and Countess of Wessex take their children out litter picking
Lady Louise is studying for her A-Levels in English, History, Politics and Drama, and while she's unlikely to take on royal duties, she could decide to accept patronages in the future.
HELLO! takes a look back at five of her biggest milestones to date.
First major public moment
While Lady Louise made her debut at Trooping the Colour in 2009, she had a starring role as one of Prince William and Kate Middleton's bridesmaids at their royal wedding in April 2011.
The then seven-year-old joined Margarita Armstrong-Jones, Grace van Cutsem, the Duchess of Cornwall's granddaughter Eliza Lopes, William Lowther-Pinkerton and Tom Pettifer in the bridal party.
MORE: How life could change for Lady Louise Windsor after 18th birthday
MORE: 18 sweet photos that show the royal cousins' close bond
Lady Louise was one of William and Kate's bridesmaids
The bridesmaids wore dresses designed by Nicki Macfarlane, accessorising with ivy and lily-of-the-valley hair wreaths.
Lady Louise shared a carriage with her older cousin, Prince Harry, following the wedding ceremony at Westminster Abbey.
First royal tour
At the age of 11, Lady Louise and her younger brother, James Viscount Severn, then seven, accompanied their parents on their first overseas engagement in South Africa.
The children joined Prince Edward and Sophie on a visit to the Ubunye Foundation, of which the Countess is patron.
Carriage driving debut
Following in her grandfather the Duke of Edinburgh's footsteps, Lady Louise made her carriage driving debut in 2017 during the Royal Windsor Horse Show, and led the carriages of the Champagne Laurent-Perrier Meet of the British Driving Society.
Making her carriage driving debut in 2017
A year later she took part in the Private Driving Singles carriage drive at the Royal Windsor Horse Show and achieved third place. In April 2021, following Prince Philip's death, it was revealed she had inherited her grandfather's driving ponies and carriage.
The young royal received her GCSE results in August 2020. Buckingham Palace did not share Lady Louise's grades, stating that they were a private matter. She is now in the second year of her A-Level studies, but her mother opened up about her daughter's education in a rare interview in June 2020, saying: "She's working hard and will do A-levels. I hope she goes to university. I wouldn't force her, but if she wants to. She's quite clever."
Sophie and her husband Prince Edward decided not to use HRH titles for their children when they were born. The Countess told the newspaper: "We try to bring them up with the understanding 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 I think it's highly unlikely."
First TV interview
Lady Louise delighted royal fans as she gave her first TV interview in September, when she opened up about her close bond with the late Duke of Edinburgh.
Speaking on BBC One's documentary, Prince Philip: The Royal Family Remembers, the teenager spoke about following in the Duke's footsteps with her love of carriage driving.
Lady Louise said: "The Duke of Edinburgh has been so involved in my driving which has been lovely, but slightly scary because he invented the sport pretty much, but it's incredible to have learned first-hand from him and definitely made us closer, I think.
"After a competition, he would always ask how he went, his eyes would light up because he would get so excited when he talks about it."
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