Prince George, Princess Charlotte and Prince Louis have made rare appearances for royal events such as Trooping the Colour and the Christmas Day service.
They have also posed for official portraits to celebrate special occasions or in photos released by Kate and Prince William.
When they have been seen, Kate appears to dress her children in the same or similar outfits.
In November 2015, Princess Charlotte was snapped in a pink floral dress and matching cardigan.
A month later, another portrait of the royal was released where she wore the same ensemble.
She has since worn floral dresses that are in the same colour and style.
Earlier this year, a picture was released to celebrate Prince George’s birthday.
The snap – taken by the Duchess of Cambridge – showed him wearing a khaki polo shirt which he was seen in the previous month.
“This sends a positive message and shows that she is unafraid to recycle classics.”
Kate and Prince William appear to value the privacy of George, Charlotte and Louis.
By recycling looks, the royals may also be trying to detract attention and speculation around their children.
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The royal line of succession – who outranks who?
The line of succession to the British throne dictates the order in which each member of the Royal Family would ascend to the throne.
It is also seen as a ranking of importance with the head of the line, the Queen, taking the place of ruler.
Older children come before younger children. Traditionally boys came before girls, but this law was changed on 26 March 2015 before the birth of Prince William’s first child.
Incredibly, Catholics are still excluded from the line of succession, as are children born outside of wedlock.
The royals, who usually stick to a strict protocol when appearing in public, often arrive at events in ascending order of importance, with the most important royal arriving last.
Prince Charles, 71, is currently second-in-line to the British throne, followed by Prince William, 38, his oldest son.
Then comes Prince William’s children, George, seven, Charlotte, five, and Louis, two, and they are followed by Prince Harry, 35. Prince Harry is succeeded by his son Archie Harrison, born in May 2019.