30 April was the birthday of former Dutch queen, Juliana, mother of the also former queen, now princess,
Beatrix. Beatrix' birthday is the 31st of January, and she didn't want the holiday to take place in winter. Also she wanted to honour her mother. So when she became queen, she chose to keep Queen's Day on the 30th of April.
In 2013 Beatrix retired and her son, Willem-Alexander, became king. He chose for the tradition to have the queen's/king's day take place on the queen's/king's birthday. In his case Queen's Day only had to move a few days: King's Day, WA's birthday, is the 27th of April, and last King's Day he celebrated his 50th b-day.
The definite queen's and king's stamps made me frown. There exist great bright photos of these people, but for the definite stamps they apparently chose for a bit colour-empty design.
The present definite King's stamp:
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Previous definite stamps of Beatrix:
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To show what nice other stamps could have been used as definite stamp, see for example this stamp sheet, issued for Willem-Alexander's 50th birthday last week:
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The photos on top have been made by his father, late prince Claus.
I don't have this sheet at home yet, so this is the picture, downloaded from the PostNL webshop's site.
See more Kings and Queens at and via today's Sunday Stamps!