Young Marius Borg Hoiby – Princess Mette-Marit's teenage son from a previous relationship – has been perfectly integrated into the Norwegian royal family for years.
And further enforcing his status in the clan, the entire group gathered together on Sunday celebrate the 15-year-old's confirmation ceremony in the church of Asker, just outside Oslo.
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Proud Mette Marit was beautifully turned out in traditional dress to watch her eldest child as he prepared to pass the threshold of manhood. Her ex-partner, Morten Borg, who is Marius' father, was also there.
Dressed in white, the teen shared his big day with 14 other youngsters and emerged from the church with a wide smile on his face.
Crown Prince Haakon was waiting to greet him and enveloped the boy in a big hug as he emerged as a grown up. King Harald and his wife Sonia also witnessed the happy scene.
And Marius' younger siblings Ingrid Alexandra, eight, and Sverre Magnus who is six, would no doubt have been taking notes for when their big day comes.
Just weeks before his confirmation, Marius' family had again put on united front to protect their son.
Norway's future king and his wife took the unusual step of writing an open letter to one of the country's newspapers, VG, justifying the teenager's use of photo sharing application Instagram.
After fears for security were raised by the publication, the couple said it was "difficult to see" how Marius brought danger on the family by uploading pictures and GPS co-ordinates of their whereabouts.
"We react strongly that you are exposing our child in this manner," they wrote.
"For us, it's very important to shield our children against an undisciplined public spotlight because we believe it can be a heavy burden and damaging. All children have a right to be protected against that."
It's a little princess!