Happy birthday Lady Louise! Royal family sends well wishes to Queen Elizabeth's youngest granddaughter

Members of the royal family have wished Lady Louise Windsor on her 21st birthday in heartfelt messages shared on social media.

Once dubbed an 'English rose that is blossoming', Lady Louise - whose parents are the Duke and Duchess of Edinburgh - is celebrating her milestone birthday at university in Scotland with her boyfriend.

However, wishes have poured in for the young royal from all over the country on Friday, November 8 - including from Buckingham and Kensington palaces.

The official X account for King Charles and Queen Camilla marked Louise's birthday with a post that read: 'Happy 21st birthday to Lady Louise!'

The tweet was reposted by Kensington Palace, with the Prince and Princess of Wales also commemorating her birthday with a tweet that read: 'Wishing Lady Louise a very Happy 21st Birthday!'

Royal fans also flooded X with birthday messages for Lady Louise, who has been hailed as as The Firm's 'secret weapon', thanks to her natural poise combined with a down-to-earth nature and resemblance to her late grandmother Queen Elizabeth II.

The beloved daughter of Prince Edward, 60, and Duchess Sophie, 59, is currently studying English at St Andrews in Scotland.

King Charles' niece is reportedly considering a career in the military and is said to have 'fallen in love' with army cadets alongside her university degree - much like her father did a generation earlier.

A source told The Sun: 'She talks about being very keen on a career in the military, serving the King and country. She is all about the Army Cadets and has fallen in love with it.'

If the 20-year-old royal, who has maintained a low profile during her university days, goes down the military path, she will be the first female royal to serve in the military since her late grandmother, Queen Elizabeth II.

While Lady Louise often shies away from the spotlight, instead keeping a firm focus on her education, she may become a rising star among the younger generation of royals as she's set to follow in the footsteps of the late Queen, with whom she was very close.

Louise, who is 16th in line to the throne, has just entered her third year at the University of St Andrews studying English and has reportedly said on her LinkedIn page that she is interested in pursuing a career in 'the military, diplomacy or law'.

Louise is also treading in the footsteps of her cousin, William, who attended St Andrews where he met his now wife, the Princess of Wales.

Set for a life of public service, with all eyes on Louise, she's making the most of her student life at St Andrews before she graduates next year.

Snaps from a fundraiser for the university's drama society earlier this year showed Louise partying with friends, showing off her moves on the dancefloor and snapping selfies with her rumoured boyfriend.

Donning a classic V-neck little black dress, she looked particularly cosy with Felix da Silva-Clamp, who she is said to have found romance with.

The duo wrapped their arms around each other, gently placing their heads together as Lady Louise took selfies on her phone, while in another image, Lady Louise is seen snuggling up to Felix, placing her hand on his chest and her head on his shoulder.

The pair have been forging a strong bond over the past two years, with Felix - whose father is a solicitor - even travelling down to the Sandringham estate in Norfolk to see Louise at her driving competition in June, where she won an impressive silver medal.

If the couple go the distance they will follow in the footsteps of William and Kate, who also met when they were students at St Andrews, and Felix already seems at ease with the family.

He appeared to get on well with Lady Louise's parents, beaming as he chatted to the Duchess of Edinburgh.

Over the years, Lady Louise has endeared herself to the British public, and members of the royal family, with a quiet confidence, sense of duty, and charm.

But the rising star's life was almost snuffed out, alongside her mother's, on the day she was born due to Sophie losing nine pints of blood through internal bleeding.

The Duchess, then 38, had suffered an acute placental abruption and was reportedly just 15 minutes away from dying in the emergency room, with her husband Edward unable to attend because he was in Mauritius for an official visit.

However she managed to give birth to Louise, who weighed just 4lb 9oz, after an emergency C-section, but she had to be transferred away from Sophie almost immediately for specialist care.

Complications from her early birth left Lady Louise with esotropia - a condition which means that both eyes do not look in the same direction - and reportedly 'completely reshaped' her mother's character.

Following a number of operations, in 2013 one of them was more successful and Sophie later explained that Louise has perfect sight now.