Prince Oscar looks adorable at mom Princess Victoria of Sweden's 39th birthday

Crown Princess Victoria of Sweden celebrated her 39th birthday with her family on Thursday (July 14), but it was one particular member who really stole the spotlight. Newborn baby boy Prince Oscar charmed the nation and royal fans worldwide as the four-month-old made a rare appearance at the festivities.

Victoria proudly held her little boy in her arms as she showed him off to well-wishers at Solliden Palace – the royal family's summer residence – on the island of Öland.

The future queen of Sweden was accompanied by her husband Prince Daniel and the couple's four-year-old daughter Princess Estelle, who looked just as sweet as her younger brother in a matching blue dress.

TAP TO VIEW GALLERYPrincss Victoria held Prince oscarCrown Princess Victoria of Sweden proudly held her little boy

The family were also joined by Victoria's parents King Carl XVI Gustaf and Queen Silvia.

The crown princess, who was radiant in a white dress and leather belt, took turns with her husband in carrying baby Oscar. At one point the little boy let out an adorable yawn as he sat in his dad's arms.

Prince Daniel holding baby Prince OscarPrince Oscar was born in early March

Victoria and Daniel also took part in a walkabout, where the popular princess was showered with gifts including food, flowers and framed photographs. Estelle also lent a helping hand, collecting her mum's presents and carefully passing them on to royal aides.

To mark Victoria's birthday nationwide, the Swedish Armed Forces fired a 21-shot salute from Skeppsholmen and the other salute stations in Sweden at twelve noon.

Princess Victoria holding hands with Princess EstelleThe family took part in a walkabout in their summer residence Solliden Palace

The last time Prince Oscar made a high-profile public appearance was at the end of May, when he was christened at the royal palace in Stockholm.

Oscar wore the traditional christening gown that his sister Estelle, his mom Victoria and other members of the Swedish royal family have worn before him. The ceremony, which was officiated by Archbishop Antje Jackelén, was steeped in tradition and as proceedings got underway, baby Oscar nodded off to sleep.

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