See the Royal Family's Sweet Wishes (and the Queen's Cute Emoji) for Birthday Boy Prince Louis!

Prince Louis is 3 — and the royal family is celebrating.

The official social media accounts for The Royal Family, which represents Queen Elizabeth and other senior members, as well as Clarence House, which represents Prince Charles and Camilla, Duchess of Cornwall, made sure to mark the birthday of Kate Middleton and Prince William's youngest child on Friday. Both pages shared the new portrait of Prince Louis sporting a backpack and big grin before he left for his first day of preschool this week. (The photo was taken by mom Kate!)

"Wishing Prince Louis a very happy third birthday today. 🚲" The Royal Family page wrote alongside the newly shared shot, complete with a bike emoji. (Although at first glance it looks appears Louis is already riding without training wheels, his red bike has no pedals, meaning it's a walking bike to help him practice balance!)

Clarence House shared the new photo in their stories with a sweet message: "Wishing Prince Louis a very happy third birthday," they captioned the snap along with a birthday cake emoji.

Last year to celebrate Prince Louis's second birthday, his grandfather Prince Charles shared a never-been-seen photo of little Louis giving him a hug.

The young prince is attending London's Willcocks Nursery School, the same school big sister Princess Charlotte attended.

A royal source told PEOPLE at the time, "They chose that nursery because they thought it would be an ideal first step for Charlotte's education, and they were impressed by the team who work there."

The nursery school is the perfect choice for Louis given that siblings Prince George, 7, and Princess Charlotte, 5, both attend Thomas's Battersea nearby.

The Duchess of Cambridge Prince Louis

Max Mumby/Indigo/Getty Kate Middleton, Prince William, Prince Louis, Princess Charlotte and Prince George

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Kate also previously shared photos of George and Charlotte on their first days of nursery school. Charlotte started Willcocks Nursery School in January 2018, while George headed to preschool at the Westacre Montessori School in Norfolk in January 2016. Louis' later start date was likely affected by the latest lockdown in the U.K. amid the ongoing COVID-19 pandemic.