The Duchess of Cambridge, wife of Britain's Prince William, is pregnant with her second child, media reported Monday.
Kensington Palace said Queen Elizabeth and members of both families were delighted with the news, BBC reported.
Prime Minister David Cameron tweeted he was "delighted by the happy news that they're expecting another baby".
The couple's second child will become fourth in line to the throne, moving Prince Harry further down the line of succession.
The announcement came two months after the couple's first child, Prince George, had his first birthday.
Unlike when she was pregnant with George, the duchess is being treated at Kensington Palace and not at a hospital.
The first pregnancy was revealed when the duchess was just a few weeks pregnant after she was admitted to hospital suffering from severe morning sickness in December 2012.
