Celebrations are in order for the Monaco royals this week as Prince Albert and Princess Charlene mark their twins' ninth birthday.
Prince Jacques and Princess Gabriella will mark their special day on 10 December 2014.
The pair were born at Princess Grace Hospital Centre, with Jacques arriving two minutes after his sister Gabriella.
Under the constitution of Monaco, the crown passes according to male-preference cognatic primogeniture meaning that Jacques is his father's heir.
The twins also have two older half-siblings from Prince Albert's previous relationships – Jazmin Grace Grimaldi and Alexandre Grimaldi.
To mark Jacques and Gabriella's ninth birthdays, we take a look back at the House of Grimaldi’s most adorable baby photos - including one of their late grandmother Grace Kelly.
© GettyGrace Kelly
At just 8 months old, Hollywood actress Grace Kelly was ready for her close-up, photographed in July 1930.
She became Princess of Monaco upon her marriage to Prince Rainier III in 1956.
The Academy Award-winning actress tragically died at the age of 52 in 1982 after a car accident.
© GettyPrince Albert
Prince Albert out for a stroll in his pushchair with his older sister, Princess Caroline, in 1959.
The prince succeeded his father as head of state in 2005.
© GettyPrince Rainier III of Monaco
Prince Rainier is pictured here at the age of seven months with his family in 1924.
He was the second child of Prince Pierre, Duke of Valentinois and Princess Charlotte (Hereditary Princess of Monaco).
Rainier also had an older sister, Princess Antoinette, Baroness of Massy.
© GettyPrince Jacques and Princess Gabriella
Less than a month after they were born, royal twins Gabriella and Jacques were introduced to the public on the balcony of the royal palace.
They were baptised at the Cathedral of the Immaculate Conception on 10 May 2015.
© GettyPrincess Caroline
Princess Caroline is pictured with her mother Grace Kelly in her nursery.
She was heir to the Monegasque throne until the birth of her brother Albert's twins, Prince Jacques and Princess Gabriella, in 2014.
© GettyAndrea Casiraghi
Baby Andrea Casiraghi yawns at his mother Caroline, as she poses for photographers in Monaco in 1982.
Caroline had three children with her second husband Stefano Casiraghi - Andrea, Pierre and Charlotte.
Stefano was sadly killed in a speed-boating accident in 1990, at the age of 30.
© GettyCharlotte Casiraghi
Caroline and Stefano pictured with their eldest son Andrea and baby daughter Charlotte on the day of her christening in 1986.
© GettyPierre Casiraghi
Princess Caroline debuts baby Pierre Casiraghi in 1987 alongside her father Prince Rainier III, her husband Stefano Casiraghi (with baby Charlotte) and brother Prince Albert (with Caroline and Stefano's older son Andrea).
© GettyPrincess Alexandra of Hanover
Princess Caroline married her third husband, Prince Ernst August of Hanover, in January 1999.
Their daughter, Princess Alexandra of Hanover, was born on 20 July 1999.
As well as Caroline's elder children, Alexandra also has half-brothers from her father's previous marriage - Prince Ernst August and Prince Christian.
© GettyPrincess Stephanie of Monaco
Princess Stephanie is the youngest child of the late Prince Rainier III and Grace Kelly - and a sister of Prince Albert and Princess Caroline.
Here she's pictured on holiday at a Swiss resort with her parents in 1965.
© GettyLouis Ducruet
Princess Stephanie and her husband, Daniel Ducruet, introduce their first child, Louis, in 1992.
The couple welcomed their second child, Pauline, two years later, but they divorced in 1996.
Stephanie also has a third child, Camille Gottlieb, born in 1998, who is not in the line of succession.
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