In a new documentary, Prince William and Prince Harry are seen laughing over the striking resemblance of a young Prince Charles to Prince George.
The royal siblings are seen poking fun at their father as they watch one of the Queen's personal films of Prince Charles as a toddler striding across the lawn at Windsor, almost marching in style.
"He walks just like George!" says Harry to William as they sit side-by-side laughing at the never-seen-before footage, which shows the Queen as a young mom, playing in the garden with Charles who wears a playsuit and classic brown leather shoes, his sister Princess Anne sitting upright in a pram.
"Or George walks like him!" adds Harry, to which William notes: "It's a purposeful walk."
Narrated by Charles, Elizabeth at 90: A Family Tribute will air Thursday as part of a birthday tribute to the Queen. It also includes footage of Charles commenting on his mother's love of horses as he watches her take part in Trooping of the Colour in 1981. When a starting pistol was fired in the air, he notes her ease in calming down the fractious horse, saying she's "made of strong stuff you know!" with a nod and a chuckle.
Harry and William also take a moment to reminisce on their own childhood as they watch Charles play with his little sister in the gardens of Windsor Castle.
"We've probably chased each other round that garden a few times as well," says William.
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"Not for a while," responds Harry, adding with a fond tone: "In the early days, when Gan-Gan was around." Presumably talking about the Queen Mother, 'Gan Gan' is also the name that Princess Kate recently revealed George uses to refer to his great-grandmother, the Queen.
The home video also includes footage of a young Elizabeth singing a song complete with adorably cute hand actions, with her sister Margaret – Lady Sarah Chatto reveals the moves were taught to them by the Queen Mother.
Elizabeth at 90: A Family Tribute will air on BBC One at 9 p.m. on Thursday.