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And the little girls certainly made the grade in their latest portraits – which will be used to grace a charity stamp collection.
With their golden locks and cherubic features – increasingly reminiscent of their vivacious Argentine mother – the three girls couldn't look cuter.
On September 26, the images will appear on stamps that are to be circulated around schools.
Sales will then go on to fund children's charities the length of the country.
The Dutch royal family have a long and proud association with the organisers, the Foundation for Children's Welfare Stamps.
The girls' father, Willem-Alexander, and grandmother, Queen Beatrix, both also posed alongside their siblings when they were young.