The young royal, who is the King's niece, is currently studying English at the University of St Andrews in Scotland.
Despite their difference in age, Lady Louise has always enjoyed a close relationship with her older cousins and younger second cousins.
While Lady Louise and her younger brother, James, Earl of Wessex have grown up out of the public eye and are not expected to carry out royal duties in future, they have joined their family at some major royal events over the years.
Take a look at some of the sweetest photos of Lady Louise and her royal relatives.
Altogether
This is one of the last public images of the late Queen Elizabeth II with some of her grandchildren and great-grandchildren.
Lady Louise has always travelled with her parents for the royal family's annual summer break in Balmoral.
And no doubt she helps to keep a close eye on the youngest royals during their get-togethers.
The Edinburghs
Lady Louise and James have joined their parents on their public engagements in the past, and we love how this photograph shows the closeness between them and their parents.
While Lady Louise shares her mother's love of sport, it seems she also has a similar sense of humour to her father, judging by their giggles!
Girl talk
Lady Louise has often joined her cousins, Princess Beatrice and Princess Eugenie, on the walk to the Easter Sunday church service.
We love the coordinating trench coats and we can't help but wonder what they're all chatting about!
Royal bridesmaid
When Prince William married Kate Middleton on 29 April 2011, Lady Louise was among their bridesmaids.
And after the ceremony at Westminster Abbey, the then eight-year-old shared a carriage with cousin Harry.
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Mum and daughter
Lady Louise shares a lovely bond with her mother, Sophie, and it's clear from way that the Duchess speaks about her daughter.
In an interview with the Times in 2020, the then Countess of Wessex spoke about her Lady Louise's education, 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!"
Lady Louise's GCSE and A-Level results were not made public but but standard entry requirements to St Andrews are AAA.
A royal role model
Like her late grandfather, Prince Philip, Lady Louise is a talented carriage driver.
Here she is teaching her second cousins, Savannah and Isla Phillips, during a ride around Windsor.
With granny
Lady Louise is the youngest granddaughter of the late Queen Elizabeth II.
The pair shared a love for equestrian sports and Sophie once revealed the incredible moment that Lady Louise realised who her grandmother was.
In a 2016 interview with the BBC's Louise Minchin, she was asked by the presenter if her children had started to acknowledge that their granny is a highly important public figure.
"It happened a little while ago," said Sophie laughing. "Well for Louise, actually, it was much more of a shock to the system. 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.'"
Sophie added: "I don't think she had grasped that perhaps there was only one Queen."
The Waleses
The Prince and Princess of Wales are close to the Duke and Duchess of Edinburgh, and here they are pictured at the Commonwealth Youth Games 2022 in Birmingham.
Princess Charlotte
Lady Louise took Charlotte under her wing when she was a special attendant at Eugenie's wedding, and cameras captured this warm greeting between the pair at the Commonwealth Games.
A royal play date
Lady Louise having fun with Savannah and Isla at the Royal Windsor Horse show in 2015.
Sweet cousin moment
How cute is this snap of Lady Louise and a little Isla running together in 2015?
Isla, who is the daughter of Peter Phillips and his former wife, Autumn, turns 12 next March!
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