In a video clip from 1985, Princes William and Harry bang enthusiastically on the keys of a piano as they take part in a photo-shoot at Kensington Palace, enjoying family life in perfect harmony.

Watched on by a glowing Princess Diana and a proud Prince Charles, three-year-old Prince William is encouraged to kiss his one-year-old sibling, Prince Harry.

William and Harry were captured on film playing the piano, as they took part in a photo-shoot at Kensington Palace in 1985

William is at first reluctant, but then lands a cheeky smacker on Prince Harry’s head to cheers from onlookers before pulling quickly away.

At one point, their father, Prince Charles is seen playing peekaboo with a handkerchief to encourage his children to look in the right direction for the camera.

William kisses Harry's head, much to the delight of his parents and other onlookers

Just like any other youngsters, Princes William and Harry display an endearingly mischievous side – scampering away, hiding under tables and squirming out of their parents’ arms.

Prince Harry, who is just learning to walk, crawls over to photographer Tim Graham to get a closer look.

“Go on Harry, go get him!”, someone, possibly Diana, calls out from behind the video camera.

Princes William and Harry 26 years after, at Westminster Abbey before William’s marriage to Kate Middleton in April 2011

The children are joined by Charles and Diana for a selection of family snaps. The late Princess of Wales, Diana radiates as she sits on the floor next to her boys.

Prince William even helps his mother re-do her make up as he lovingly dabs her face with a powder pad.

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