Royal response from Her Imperial and Royal Highness The Princess of Prussia on the occasion of her 43rd Birthday.
Born Sophie Johanna Maria on 7th March 1978 in Frankfurt, West Germany to Their Serene Highnesses Franz-Alexander and Christine, The 6th Prince and Princess of Isenburg.
She married His Imperial and Royal Highness Georg Friedrich, The Prince of Prussia, Head of House of Hohenzollern de jure Emperor of Germany.
The reply is in the form of a card in German signed by Her Imperial and Royal Highness and also includes a photo of the couple that is signed by both of them.
Picture
Card
Translation
Thank you very much for the good wishes on my birthday. I’ve been very happy about it.
RoyalResponses 
Hello, which is the correct title to use for Princess Sophia of Prussia?.
Or how you addressed her when you wrote to her?
The address is
Burg Hohenzollern
D-72379 Burg Hohenzollern
Germany ?
Many Thanks for help
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Her Imperial and Royal Highness The Crown Princess of Prussia
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