Prince William and his wife Kate Middleton are expecting a baby in July, it was announced Monday.
This puts an end to speculation that the Duchess of Cambridge may be having twins.
The baby's sex is not known, but the Brits aren't taking any chances.
The government is set to pass legislation changing rules of succession to ensure the baby will become third in line to the British throne behind William, 30, whether the child is a girl or a boy.
The pregnancy was revealed in December when Middleton, 31, was admitted to a hospital for a type of morning sickness that is more common among women expecting twins.
Spoof Twitter accounts belonging to fictional members of the royal family have already seized on the baby news.
"One can confirm that William and Kate's baby is growing faster than the economy," wrote a "Prince Charles" on Twitter, who has more than 300,000 followers.