A tweet from Reza Pahlavi, eldest son of the last shah of Iran:
My condolences to the family of Robin Williams. He created so much laughter and joy with his brilliance, & he will be missed. Rest in peace.
— Reza Pahlavi (@PahlaviReza) August 12, 2014
(If I find more royal comments on the death of Robin Williams, I'll add them to this post.)