Queen Juliana taking part in a domestic arts class at Pimlico School during a trip to London, April 13, 1972. From this photo, it seems that Princess Beatrix’s penchant for large, voluminous, brimless hats might have been an inherited one.
Royal Hats
The Bold, Beautiful and Bizarre World of Royal Millinery
Royal Hats 
Queen Juliana’s hat is definitely an inspiration for her daughter’s cake hats. I can’t like this hat.
It’s an early cake hat IN a cooking class! Too cute.
It really does look like an early version of one of Beatrix’s cake hats.