Willem-Alexander of the Netherlands1967 Born Thu, 27 April 1967 University Medical Center, Utrecht Details Parents King of the Netherlands Willem-Alexander Claus George Ferdinand Age: 57 years, 6 months, 25 days father Klaus-Georg von Amsberg 1926 - 2002 mother Beatrix of the Netherlands 1938 Siblings Brother Friso of Orange-Nassau 1968 - 2013 Brother Constantijn of the Netherlands 1969