Kate Middleton may be known these days for her brunette hair (opens in new tab). Young Kate was blonde, the Cambridges revealed on Instagram on Sunday. To celebrate Father's Day, the royal family released a childhood photo of Kate with her father, Michael Middleton, and a snap of Prince William and Prince Charles; the second photo is from the following post:

The Cambridges celebrated Father's Day and William's 38th birthday on Sunday It was a very busy weekend for the couple. To mark the occasion, they shared a very cute series of photos with William and their three children: Prince George, Princess Charlotte, and Prince Louis.

In the first photo, posted Saturday, William sits on a swing with Prince Louis on his lap, while Charlotte and George balance behind him. Kate captioned the photo, taken by Kate, "The Duke and Duchess of Cambridge are delighted to share this new photo of the Duke, Prince George, Princess Charlotte and Prince Louis ahead of the Duke's birthday tomorrow."

On Sunday, Kate and William released two more photos of the three mini Cambridges superimposed on their father. Stay tuned:

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