It’s a tradition that royal fans look forward to every year and the 2020 Cambridge Christmas card has already been leaked by one eager follower.

An unseen snap of Prince William and Kate Middleton posing with their three adorable children, Prince George, Princess Charlotte and Prince Louis has popped up online.

According to Hello!, the card was sent to NHS staff to thank them for their work amid the coronavirus pandemic.

"To all the amazing NHS staff," a message inside reportedly reads. "Wishing you a very Happy Christmas and New Year."

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All five family members look delighted as they can be seen beaming at the camera, however, it’s Prince Louis who has really stolen the show.

The two-year-old can be seen sitting front and centre in the snap, howling laughing as one hand holds on to his dad Prince William’s leg and the other comes up to his face in delight.

Meanwhile, Prince George appears to have grown quite a bit as he sits perched with his arm on Prince William’s knee while Princess Charlotte sits on mum Kate Middleton’s lap.

According to body language expert Judi James, the photo tells a lot about the family’s dynamic.

“Kate looks very much the leader of the pack, sitting upright like the backbone of the family and greeting the camera with direct eye contact that signals high levels of confidence”, she told The Sun.

“Charlotte is challenging her mother’s role as the most confident-looking member of the family group here.”

Royal fans gushed over the photo online, with one person writing: “Beautiful family picture.”

“Lovely picture they are a beautiful family and Louis is so adorable with their smiling ,” another said.

However, one person said the setting for the photo seemed a bit odd.

“Why sit in the woodpile? Strange choices for a holiday photo.”

Another person disagreed, saying the wood in the back made the photo more relatable.

“This is such a nice pic. Very in the moment pic. Prince Louis, you are such an action person. Love, love this,” they said.

The leaked photo comes just hours after the Cambridge children made their red carpet debut over the weekend.

The children looked thrilled to be attending a special pantomime performance of Pantoland at London's Palladium Theatre hosted by The National Lottery, to thank key workers and their families for their efforts throughout the COVID-19 pandemic.

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