You have to see this adorable video of Prince William and Prince Harry as toddlers

They might have some major responsibility on their shoulders these days, but a new video serves to remind us that Prince Harry and Prince William were once a pair of adorable toddlers.

Harry uploaded the footage, which features the duo Royals aged three and one playing the piano at their Kensington Palace apartment and generally causing a bit of chaos.

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William is clearly the ringleader – aside from yelling at Harry not to step on his foot, he can also be seen climbing around underneath the piano while his younger sibling gleefully bashes away at the keys.

Princess Diana and Prince Charles also make an appearance in the video, with Charles playfully playing a game of hide and seek with Harry by covering his head with a napkin.

The unusually candid moment is a reminder of the happy family that once was.

But while Diana is no longer alive, Prince Harry is adamant that he and William will keep her legacy going.

"All I want to do is make my mother incredibly proud," he said earlier this year. "That's all I've ever wanted to do.

"When she died, there was a gaping hole, not just for us but also for a huge amount of people across the world. If I can try and fill a very small part of that, then job done. I will have to, in a good way, spend the rest of my life trying to fill that void as much as possible. And so will William."

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