Queen Maxima's daughter Princess Alexia makes royal first

King Willem-Alexander and Queen Maxima were joined by their two eldest daughters for Prince's Day (Prinsjesdag), the opening day of the Dutch parliament on Tuesday.

Princess Catharina-Amalia, 19, and Princess Alexia, 18, joined their parents at the formal event in the Hague, and for Alexia, it marked a special royal first.

The teenager looked beautiful in a raspberry pink Zhivago gown with diamond earrings and a floral hair accessory, but she also wore The Order of the Netherlands Lion for the very first time. See the Dutch royals' arrival in the clip below...

Alexia was appointed a Knight Grand Cross of the Order of the Netherlands Lion and a Knight of the House Order of the Golden Lion on her 18^th birthday on 26 June.

Earlier this month, she also carried out her first solo engagement, attending the naming ceremony of vessel VOX Alexia in Rotterdam.

It comes after Alexia graduated from the United World College of the Atlantic (UWC Atlantic College) in Llantwit Major in Wales in May, where she completed the two-year International Baccalaureate programme.

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Meanwhile, Catharina-Amalia, who is a student at the University of Amsterdam, looked elegant in a cobalt blue asymmetric gown by Safiyaa. She styled her blonde locks into an updo and accessorised with a headband and sapphire drop earrings.

The princesses' mother, Queen Maxima, opted for a blush pink Claes Iversen trouser suit with a patterned overcoat and a striking floral hat.

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The king and queen were also joined by Willem-Alexander's younger brother, Prince Constantijn and his wife, Princess Laurentien.

Willem-Alexander and Maxima's youngest daughter, Princess Ariane, 16, did not attend the event as she is currently studying at UWC Adriatic in Italy.

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Catharina-Amalia and Alexia could be among the guests at Prince Christian of Denmark's 18th birthday gala dinner at Christiansborg Palace in Copenhagen on 15 October.

The Dutch royal family share a close friendship with the Danish, Swedish and Norwegian monarchies, with Crown Princess Victoria of Sweden being one of Catharina-Amalia's godparents.

© Patrick van Katwijk

Both Princess Catharina-Amalia and Prince Christian were among the young bridal at Crown Princess Victoria and Daniel Westling's wedding in 2010.  

Now listen to HELLO!'s A Right Royal Podcast and find out more about the British royal family's favourite holiday destinations...