Prince Albert was joined by his children, seven-year-old twins, Prince Jacques and Princess Gabriella, as the Monaco royals marked Sainte Dévote Day.
Festivities kicked off on Wednesday with the family setting alight to a sailboat to celebrate their patron saint. A mass will also take place on Thursday.
The children were wrapped up against the January chill, with Jacques donning a suit and jacket to match his father, and Gabriella wearing a grey tweed dress with an electric blue furry coat.
Albert, 63, was also accompanied by his sister Princess Caroline of Hanover and his nephew Louis Ducruet.
WATCH: Monaco royal family celebrates National Day
His wife, Princess Charlene, who turned 44 on Tuesday, missed the traditional ceremony with the Princely Palace sharing an update about the royal's health on Thursday.
In a statement it revealed that the princess is recovering well, but that she will still need to rest and receive dental treatment for a few more weeks, and as a result is unable to attend this year's Sainte Dévote celebrations.
Prince Jacques and Prince Albert took part in the traditional ceremony
It added that Charlene sends her best wishes to the people of Monaco and as soon as her health permits, she looks forward to spending time with the Monegasques.
Last month, Albert shared an update on Charlene's recovery, revealing that she was "recuperating in a satisfactory and reassuring manner," as she received treatment at a facility outside of Monaco.
The family also visited Charlene during the Christmas holidays.
The young royals were joined by their aunt, Princess Caroline
Charlene shared her first Instagram post of the year on her birthday, as she reposted a video made to commemorate her special day.
The royal's initiative, the Princess Charlene of Monaco Foundation South Africa, honoured her with a video that featured childhood photographs and highlights from her life, including her Olympic swimming career and her marriage to Prince Albert.
The Prince's Palace of Monaco also shared the same video on its official Facebook page.
Charlene only returned to Monaco in November after being grounded in South Africa for six months with an ear-nose-throat (ENT) infection.
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