Crown Prince Willem-Alexander of the Netherlands' 40th birthday bash at the weekend was a blue-blooded affair through and through as regal guests from all over Europe arrived to help him celebrate. There were three princesses who stood out from the rest, though. Willem's daughters - Catharina-Amalia, Alexia and Ariane, pretty as a picture in matching pink outfits - were undoubtedly the stars of the night.
Travelling with their parents in a horse-drawn carriage the trio made a grand entrance at the relatively low-key party in the central Netherlands' grand stately house, Het Loo. While the birthday boy took charge of his youngest, four-month old Ariane, Princess Maxima - elegant in a strapless fuchsia gown - walked hand-in-hand with three-year-old Catharina-Amalia and Alexia, two, up the red carpet to the Baroque retreat's entrance.
And making the ball a truly family occasion was Willem's mum, Queen Beatrix, who led the official party portrait, when the some 50 guests gathered on the steps to the former royal summer residence. Among them were the Crown Prince Haakon of Norway and his wife, Princess Mette-Marit, who arrived with Crown Princess Victoria of Sweden. The Spanish heir, Prince Felipe and his wife, Princess Letizia put in a stylish appearance at the festivities, too.
Also at the party - which was originally intended to have taken place closer to Willem's April 27 birthday, but was postponed due to the arrival of his third daughter Ariane on April 10 - were British royals Prince Edward and Sophie, Countess of Wessex. The 42-year-old royal - who recently announced she is expecting her second child - was on radiant form in a floor-length strapless number, with the beginnings of a baby bump starting to show.