Many avid royal fans will remember Lady Louise's sweet smile from Duchess Catherine and Prince William's 2011 royal wedding.
To this day, photos of the angelic blonde seated in a horse-drawn carriage next to her cousin Prince Harry still warms our heart.
The now 14-year-old is the eldest child of Prince Edward and his wife Sophie, Countess of Wessex.
Lady Louise recently stepped out for the British Royal Family's annual Easter church service at St George's chapel, in Windsor.
And it's clear the Queen granddaughter is growing up in front of our eyes.
Channelling her grandmother's panache for bright colours, the teen looked sublime in an deep purple overcoat, teamed with a floral head piece and nude suede Mary-Jane heels.
Sophie was accompanied by her parents and little brother, James Viscount Severn.
Then and Now
Lady Louise's role at Kate Middleton and Prince William's wedding
Lady Louise was only eight years old when she made her global debut as one of the bridesmaids at the Duchess Catherine of Cambridge's wedding to Prince William in 2011.
The youngster was joined by Margarita Armstrong-Jones, Grace Van Cutsem, Eliza Lopes, and pageboys Tom Pettifer and William-Lowther Pinkerton.
Lady Louise's dramatic entrance into this world
The only daughter of Prince Edward, Earl of Wessex, and Sophie, Countess of Wessex was born on 8 November 2003.
Sophie was rushed to hospital a month before her due date and at the time, Prince Edward was on a royal tour of Mauritius.
Lady Louise was born prematurely and there were some serious complications around her birth.
It was reported that a placental abruption caused severe blood loss to both Countess Sophie and Lady Louise.
Royal Surgeon and Gynaecologist Marcus Setchell performed an emergency Caesarean section.
Lady Louise's royal title and succession to the throne
The royal parents officially announced their daughter's name on the 27th of November 2003, giving her the moniker Louise Alice Elizabeth Mary Mountbatten-Windsor.
When Sophie and Edward married in 1999, they decided they wanted their future children to lead a normal life - opting to drop "HRH" titles, which is why Louise has the title "Lady."
The granddaughter of Queen Elizabeth II and Prince Philip is currently 11th in line of succession for British throne.
She'll move to 12th once the Duchess Catherine and Prince William's royal baby arrives.
Lady Louise's eye condition
The young royal was born with esotropia, a condition that turns the eyes outwards.
The illness saw her undergo her first surgery at just 18 months - unfortunately it was not successful.
Growing up, she faced issues with her vision, which lead to her parent's decision for her to have a second operation in 2014.
It has been reported that it was a success and now Lady Louise has perfect vision.
Speaking of her daughter's condition, Countess Sophie shared, "Premature babies can often have squints because the eyes are the last thing in the baby package to really be finalised."
"Her squint was quite profound when she was tiny and it takes time to correct it. You've got to make sure one eye doesn't become more dominant than the other but she's fine now—her eyesight is perfect," she added.
Her daughter's ailment inspired the Countess of Wessex to become a patron of the International Agency for the Prevention of Blindness and a global ambassador for Vision 2020 — a worldwide initiative to eliminate avoidable blindness by the year 2020.
Lady Louise had no idea her granny was the Queen
One of the most charming facts about the teen is the fact that she didn't realise she was royalty.
Her mother sat down for a chat with the BBC, recounting the hilarious moment her daughter figured out her grandmother and the Queen were the same person.
"Well, for Louise, actually, it was much more of a shock to the system," the proud parent recalled.
"It was only when she was coming home from school and saying, 'Mummy, people keep on telling me that grandma is the queen.' And I asked her, 'Yes, how does that make you feel?' And she said, 'I don't understand...' I don't think she had grasped that perhaps there was only one Queen."
The story resonated with Sophie and Edward's desire for their children to lead a normal life.
"They're going to have to go out and get a job and earn a living later on in life," Sophie has said.
"If they've had as normal a start in life they possibly can get, then hopefully that will stand them in good stead."
Lady Louise Windsor is a keen carriage rider
Lady Louise Windsor shares her grandparents' love of equestrian sport carriage driving.
Last year, she competed in the British Driving Society Championship for Young Driver.
Prince Philip is exceptionally proud of his granddaughter, given his passion for the sport, which he took up when he was 50.