Princess Alexia turns 13

Princess Alexia, King Willem-Alexander and Queen Maxima's middle daughter, is celebrating her 13th birthday today.

Alexia attends the Christian Gymnasium Sorghvliet in The Hague, along with her older sister Amalia. Her hobbies include hockey, horse riding, singing and playing guitar, according to the Royal House.

As Alexia is not the crown princess, it is not mandatory to hang flags on government buildings for her birthday, according to the Telegraaf. But anyone who wants to do so, is allowed.