The four-month-old tot was baptised at Drottningholm Palace's church just outside Stockholm, with the family greeting the media after the ceremony.
Prince Julian Herbert Folke, Duke of Halland, who was born on 26 March, was dressed in the christening gown worn by his father to his own baptism in 1979. The family heirloom dates back to Prince Gustaf Adolf's christening in 1906 and has been worn by royal babies since.
WATCH: The sweetest photos and moments from Swedish royals' christenings
Proud mum Princess Sofia looked beautiful in a floral A-line long puff-sleeve maxi dress by Etro for her son's christening, while her husband, Prince Carl Philip, wore his military uniform.
The couple were also joined by their eldest sons, Prince Alexander, five, and Prince Gabriel, three, who looked adorable in matching navy shorts, white shirts and cream blazers.
Among the guests were Carl Philip's parents, King Carl XVI Gustaf and Queen Silvia, and his siblings and their spouses; Crown Princess Victoria and Prince Daniel, Princess Madeleine and Christopher O'Neill.
Prince Julian was christened on Saturday
Prince Julian's older cousins were also in attendance, including Crown Princess Victoria's children, Princess Estelle, nine, and Prince Oscar, five, and Princess Madeleine's children, Princess Leonore, seven, Prince Nicolas, six, and Princess Adrienne, three.
The Swedish royal family have been spending their traditional summer break together at Solliden Palace on Öland island, off the southeast coast of Sweden. The royal household shared a fun family photo as the king and queen were reunited with their children and grandchildren.
Princess Sofia looked gorgeous in her dress
In 2019, King Carl XVI Gustaf made changes to the royal house, meaning that Carl Philip and Sofia's children, as well as Princess Madeleine and Chris O'Neill's children, would lose their HRH style and in the future when they are older, would not be expected to perform duties incumbent on the head of state.
Unlike his older royal cousins, Prince Julian is the king's first grandchild to be born without the style of Royal Highness.
He is currently seventh in line to the Swedish throne behind his older brothers, Alexander and Gabriel.
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