Why Prince Louis' 5th Birthday Portraits Are Breaking Tradition Revealed

Prince Louis is turning 5 — and the royal family is celebrating his birthday with new photos.

Kate Middleton and Prince William's youngest child will celebrate his 5th birthday on Sunday, and the proud parents marked the occasion by releasing new portraits. The two snaps were taken by photographer Millie Pilkington earlier this month.

'Someone's turning 5 tomorrow… 🎂 🥳 A very happy birthday to Prince Louis,' they captioned the post on Instagram.

The first photo features Prince Louis smiling as he sits inside a wheelbarrow on top of grass and leaves as his mother, in a striped black and white top, is seen taking him for a ride. The young royal wore a blue sweater over a checkered shirt and shorts.

A second photo shows a close-up shot of Louis flashing a smile as he looks off into the distance. The slightly slanted shot gives a closer look at his light brown eyes and hair pushed back from his face.

In a break from tradition, the Princess of Wales did not get behind the camera for the new images of her son. Kate, who has previously described herself as an 'enthusiastic amateur photographer,' regularly takes photos of her three children that are released to the public for their birthdays.

On Friday, on what would have been Queen Elizabeth's 97th birthday, the palace released a of the late monarch with some of her grandchildren and great-grandchildren taken by Kate at Balmoral last summer.

To mark Prince Louis' 4th birthday last year, Prince William and Princess Kate shared four pictures of their son playing on the beach near the family's country home in Norfolk. Bearing a striking resemblance to both brother Prince George, now 9, and sister Princess Charlotte, now 7, Louis sprinted in front of the camera with a smile on his face and playfully held a cricket ball in the images.

Prince Louis' third birthday coincided with his first week of nursery school. In the portrait released for the occasion, he was all smiles sporting a backpack and posing on his red bike ahead of his first day at London's Willcocks Nursery School, the same school big sister Princess Charlotte attended.

Prince Louis has had an exciting year. In addition to starting at a new school with his siblings in September, he has also made his debut at several events alongside the royal family. He made his first outing with the royals for Christmas in December, joining them for their annual church visit, and made a similar appearance earlier this month to attend Easter Sunday mass.

Louis also made headlines in June, when he celebrated his great-grandmother Queen Elizabeth's Platinum Jubilee (marking her 70 years on the throne) at a number of events. At Trooping the Colour, the prince rode in a carriage procession for the first time and appeared on the palace balcony, instantly becoming a meme for making funny faces, chatting with the Queen and covering his ears as planes flew overhead.

Prince Louis was the star of the show again at the Platinum Jubilee Pageant, sitting on Grandpa Charles' lap and making faces at mom Kate.

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Kate and Prince William ended the four days of celebrations by sharing a social media post — and they couldn't help but acknowledge their child's scene-stealing antics.

'What a fantastic weekend of celebrations. Seeing people across the nation coming together with family, friends and loved ones has been extremely special,' they wrote. 'Thank you to everyone who turned out to show their gratitude to The Queen and her inspiring 70 years of leadership. From the crowds on the Mall to communities hosting street parties up and down the country, we hope you had a weekend to remember.'

The couple then quipped, 'We all had an incredible time, especially Louis…' with the eyes emoji.