Prince Louis Is All Grown Up in Royally Sweet 6th Birthday Portrait

Prince Louis is once again stealing the show—this time, for an extra special reason.

After all, Prince William and Kate Middleton's youngest child is celebrating his 6th birthday on April 23.

For the occasion, the Prince and Princess of Wales—also parents to Prince George, 10, and Princess Charlotte, 8—shared a new portrait of Louis, taken by his mom.

"Happy 6th Birthday, Prince Louis!" William and Kate captioned the post on their joint Instagram account. "Thank you for all the kind wishes today."

While the family hasn't publicly shared how they're celebrating Louis' birthday this year, his milestone comes amid a trying chapter for the royals. 

In fact, it was exactly a month ago that Kate—who's been away from the spotlight amid her health journey—shared that she'd been diagnosed with cancer.

"I wanted to take this opportunity to say thank you, personally, for all the wonderful messages of support and for your understanding whilst I have been recovering from surgery," the 42-year-old said in a video message March 22, which was her first formal appearance since undergoing abdominal surgery in January. "It has been an incredibly tough couple of months for our entire family."

"In January, I underwent major abdominal surgery in London and at the time, it was thought that my condition was non-cancerous," she continued. "The surgery was successful."

However, tests after the operation found that cancer had been present.

"My medical team therefore advised that I should undergo a course of preventative chemotherapy and I am now in the early stages of that treatment," Kate added. "This of course came as a huge shock, and William and I have been doing everything we can to process and manage this privately for the sake of our young family."

As Kate continues to recover, William, 41, returned to the spotlight April 18 for his first public engagement since his wife shared her cancer diagnosis.

"Oh, some cards, you're very kind," he said to fellow Surplus to Supper volunteer Rachel Candappa in a video posted to X. "Thank you very much."

For more updates on the royal family, including King Charles III's cancer battle, keep reading...

The queen consort attended the Royal Maundy Service on March 28 in place of King Charles III, making her the first spouse of the Monarch to continue the ancient tradition.

In a March 22 video message, the Princess of Wales shared that she'd been diagnosed with cancer after undergoing abdominal surgery in January.

"It was thought that my condition was non-cancerous. The surgery was successful," she said before noting that tests after the operation found cancer had been present. "My medical team therefore advised that I should undergo a course of preventative chemotherapy and I am now in the early stages of that treatment."

After photo agencies pulled the picture Kensington Palace shared of Kate since having her abdominal surgery on March 10, the Princess of Wales addressed claims the photo was doctored. 

"Like many amateur photographers, I do occasionally experiment with editing," she tweeted on March 11. "I wanted to express my apologies for any confusion the family photograph we shared yesterday caused. I hope everyone celebrating had a very happy Mother's Day. C."

Princess Diana's niece celebrated Mother's Day in the U.K. by sharing she and her husband Michael Lewis privately welcomed their first baby.

“It’s the joy of my life to be your mummy, little one. I love you unconditionally," she captioned her March 10 Instagram post. "Happy Mother’s Day to those who celebrate today."

After keeping up her full slate of engagements in the wake of her husband's cancer diagnosis, the palace cleared Camilla's schedule.

The Times pointed out March 2 that the 76-year-old didn't have any engagements on her calendar until March 11, when she'd be due at Westminster Abbey to observe Commonwealth Day.

The husband of Lady Gabriella Windsor and ex-boyfriend of Pippa Middleton, was found dead Feb. 25. Days later, a coroner's inquest found that he died by suicide.

While King Charles III was in the hospital for his benign prostate enlargement procedure, the royal family member was diagnosed with cancer.

"His Majesty has today commenced a schedule of regular treatments, during which time he has been advised by doctors to postpone public-facing duties," Buckingham Palace said Feb. 5. "Throughout this period, His Majesty will continue to undertake State business and official paperwork as usual.The King is grateful to his medical team for their swift intervention, which was made possible thanks to his recent hospital procedure. He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible."

The Duchess of York's rep said in a statement on Jan. 21 that Sarah was recently diagnosed with malignant melanoma, an aggressive form of skin cancer. Several months prior, she underwent a single mastectomy to treat breast cancer.

On Jan. 14, Queen Margrethe II of Denmark made history as she officially abdicated the throne, handing the crown over to her son, now known as King Frederik the 10th. 

Kensington Palace announced on Jan. 17 that Kate Middleton underwent planned abdominal surgery and was set to remain in the hospital for 10 to 14 days.

"Based on the current medical advice," the Palace said, "she is unlikely to return to public duties until after Easter."

Amid Kate's recovery, Prince William postponed a number of engagements as he supported his family, including the couple's three children, Prince George, Princess Charlotte and Prince Louis.

Shortly after Kate's hospitalization was made public, Buckingham Palace shared that Charles "has sought treatment for an enlarged prostate."

"His Majesty's condition is benign and he will attend hospital next week for a corrective procedure," the statement added. "The King’s public engagements will be postponed for a short period of recuperation."

Princess Claire and Prince Felix of Luxembourg welcomed son Balthazar Felix Karl on Jan. 7, the first royal baby of the New Year!