Queen Maxima's daughter Princess Alexia enters a new decade in her life

Goodbye teens, hello twenties! Queen Maxima and King Willem-Alexander of the Netherlands' daughter Princess Alexia entered a new decade on Thursday (June 26), turning 20.

The Dutch Royal House marked the Princess' birthday with a photo of her that was seemingly taken in April at this year's King's Day celebration. Alongside the picture on Instagram, the Royal House wrote (translated to English), "Princess Alexia celebrates her 20th birthday today."

The 20 year old returned to the UK last September to begin her studies at the University College London. The Royal House revealed in November that Alexia had "switched" from pursuing a bachelor's degree of "science & engineering for social change" to a bachelor's degree in civil engineering.

Alexia took a gap year after obtaining her International Baccalaureate diploma from UWC Atlantic in Wales, which she and and Spain's Princess Leonor both graduated from in 2023. At King's Day 2024, the Princess shared (via RTL) that her gap year had included "a little work" and "a little travel." She said, "In a gap year like this, every moment is special. I enjoyed everything very much." 

Alexia, who is second in line to the Dutch throne, is King Willem-Alexander and Queen Maxima's second child. Their Majesties are also parents to 21-year-old Princess Catharina-Amalia and 18-year-old Princess Ariane, who graduated from UWC Adriatic last month. 

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Amalia was out with her parents earlier this week. The Princess of Orange joined her mom and dad at a dinner for heads of state and government who were attending the 2025 NATO summit in The Hague. Before the dinner at Huis ten Bosch Palace, the heir to the Dutch throne welcomed guests alongside the King and Queen, including American President Donald Trump. Maxima was filmed introducing her firstborn to the 45th and 47th president of the United States. At the dinner, Amalia was seen sitting next to French President Emmanuel Macron.

The following day, King Willem-Alexander told RTL Boulevard, via AD, that Amalia wanted to be at the dinner. His Majesty said (translated to English): "She had good conversations, she really enjoyed it. She can handle it easily, she is a very good co-hostess for us."