Monaco's royal twins: Only one will get the throne.

PARIS, Safar 18, 1436, Dec 10, 2014, SPA -- Monaco is expecting a double dose of royal babies this month, but only one twin will get to be the principality's future ruler, according to AP.

Her Serene Highness Princess Charlene, 36, is giving birth to twins but the doctor delivering them will have no more than a symbolic hand in deciding the destiny of the Grimaldi dynasty, authorities say.

Prince Albert II, the 56-year-old son of the late American actress Princess Grace, had some subjects worried by his long bachelorhood and his lack of an heir since his two previous children were born out of wedlock and are not eligible for the throne. Then prince married Charlene Wittstock, a Zimbabwe-born, South Africa-raised former Olympic swimmer, in 2011.

Now the tiny royal state on the Riviera has two reasons to rejoice.

The babies will be the first twins in the royal household, which dates to the 13th century, but they will not share the throne. Albert says the first one out will be first in line, unless a boy and a girl emerge, in which case the boy becomes the royal heir, reflecting the male priority of Monaco's laws of succession.

-- SPA

20:55 LOCAL TIME 17:55 GMT

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