The son of Swedish Princess Madeleine and her British-American husband Christopher O'Neill celebrated his sixth birthday five days after his proud mom turned 39
prince Nicolas
Prince Nicolas
| Credit: Princess Madeleine of Sweden/ instagram

Sweden's Prince Nicolas is 6 years old and spending his days soaking up the sun!

Princess Madeleine of Sweden's second child celebrated his birthday on Tuesday - just five days after Madeleine herself turned 39 on June 10.

The proud mom shared a sweet snap of her only son on Instagram, writing, "Happy Birthday, dear Nicolas! We love you to the moon and back. Keep on truckin'! 🎉❤️🚜"

Madeleine and her family of five with her British-American husband Christopher O'Neill (Nicolas is the middle child between sisters Princess Leonore, 7, and Princess Adrienne, 3) have lived in the U.S. since relocating to Florida from Sweden in the fall of 2018.

Since then, the grandson of Sweden's King Carl XVI Gustaf and Queen Silvia has enjoyed a sun-kissed beach life, and Prince Madeleine has often shared adorable photos of her three children embracing American holidays, including celebrating July 4 and dressing up for Halloween.

It was announced in 2019 that King Carl XVI Gustaf had decided to strip the royal titles of his grandchildren, including Princess Madeleine's three children and her brother Prince Carl Philip's three sons with wife Princess Sofia. As a result, they are no longer official members of the royal house and are no longer expected to perform official royal duties. And though Madeleine and Carl Philip's children have retained their Prince and Princess titles, these titles will become personal and any future spouses or children will not have a right to them.

Princess Madeleine responded at the time of the official announcement, writing on social media: "This change has been planned for a long time. Chris and I think it's good that our children are now getting a greater opportunity to shape their own lives as private individuals in the future."

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Princess Madeleine previously opened up to PEOPLE about her "normal" life as a mom in 2016: "They wake me up and we fix breakfast together and the breakfast flies all over the place! And then we go out to the park and we swing, we try to do a lot of activities because my little Leonore, she has lots of energy, so we have to keep her stimulated and busy."