Prince Albert the second and Princess Charlene of Monaco welcomed a set of royal twins -- but only one will be the future heir to the throne.
Forty-two cannons were fired in honor of the twins, who were born via a cesarean section at the Princess Grace Hospital, name for Albert's mother, Grace Kelly.
The twins are the first children for Princess Charlene, a 36-year-old former South African Olympic swimmer. Prince Albert, 56, has two older children who are considered illegitimate by the House of Grimaldi.
The princess gave birth to Gabriella at 5:04 and Jacques at 5:06. Though he was born second, Jacques is the crown prince thanks to the Mediterranean's male inheritance laws.
Albert reportedly didn't know the sex of the children before birth. "It is one of the beautiful surprises that life offers us," he said.
Still, Monaco's succession laws give priority to boys. The only woman ever to reign was Princess Louise-Hippolyte in 1731. If both twins had been girls, the baby born first would have taken the throne.
In 2002, Monaco's parliament changed its constitution so that royal power could pass from a reigning prince with no descendants to his siblings-possibly Albert's two sisters, if he did not have legitimate heirs.
The royal household dates back to the 13th century, but Jacques and Gabriella are its first twins-but they're hardly the first royal twins in Europe.
King James I of Scotland and his wife Joan Beaufort had the United Kingdom's lone pair in 1430, and many more across the pond have followed. In 2013, the Prince of Prussia Georg Fredrich and his wife Princess Sophie of Isenberg had twin boys. In 2011, Crown Prince Frederik of Denmark and his wife Mary had twins, and the year before, the Duke of Anjou, Prince Louis Alphonse, and his wife Maria Margarita Vargas Santaella had their own.
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