Fans were delighted by the “fantastic” photo and heartfelt message, with many taking the opportunity to wish Prince William a happy birthday.

“What a fun photo!! Love it. Happy birthday to Prince William!” one fan wrote.

“The best bday photo I’ve seen. Happy Bday Prince William!”

“Possibly the best picture I’ve seen of the family,” commented another.

“Fantastic Birthday. Such an adorable family photo.”

“What a fabulous photo. You can feel the love and joy in this family. Happy Birthday Prince William.”

While royal fans were enthusiastic to celebrate Prince William’s birthday they were equally excited for a previous post from Princess Catherine when she announced a welcomed health update.

In the update, Catherine announced that she is “making good progress” in her cancer battle while confirming her attendance at the Trooping the Colour ceremony.

In her first official statement since revealing her cancer diagnosis earlier this year, Catherine expressed her gratitude to supporters for their encouraging words and provided an update on her recovery.

To accompany her latest message, a new photo of the Princess was released, showing her looking well in a jacket and jeans, standing under a tree on the Windsor estate.

“I have been blown away by all the kind messages of support and encouragement over the last couple of months. It really has made the world of difference to William and me and has helped us both through some of the harder times,” she began.

“I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days. On those bad days you feel weak, tired and you have to give in to your body resting. But on the good days, when you feel stronger, you want to make the most of feeling well.

“My treatment is ongoing and will be for a few more months. On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home.”