It's a girl!

The princess, who is fourth in line to the throne, slept in her mother's arms during the first public appearance on the steps of St Mary's Hospital in London. Royal couple will stay at Kensington Palace for a few days, before decamping to their country home Anmer Hall in Norfolk.

Prince William and Kate Middleton's second child, a baby girl, was born on May 2, 2015, at 08:34 a.m. local time. The mother and the baby were doing quite well, Kensington Palace tweeted. "The Duke of Cambridge was present at the birth," it said in a statement.

The Duchess of Cambridge, Lady Catherine or Kate Middleton, as she was known before marrying Prince William, was seven days overdue with the baby. Kate traveled by car to the hospital and was admitted at 06:00 a.m. at the hospital.

The baby was born in the private Lindo Wing of St. Mary's hospital in Kensington, west London. Mother Kate and the baby, which weighed 3.7 kilograms, "are doing well," Kensington Palace said. "The Queen, the Duke of Edinburgh, the Prince of Wales and the Duchess of Cornwall, Prince Harry and members of both families have been informed."

Fans are eager to see what 32-year-old William and 33-year-old Kate's baby girl looks like, but that may take time. The royal couple appeared much later in front of the press after baby George was born. George's sister signifies a new period for the couple, with Prince William adjusting to his new job as a helicopter ambulance pilot.

Betting on the baby's name has begun in earnest. All the top bets were for girls' names, with Alice and Charlotte leading the list. Speculations on the royal couple having a girl rose after Prince Charles signaled he would like a granddaughter this time.

This is the first time in over 60 years that the monarchy will have a princess this high in the line of succession. The baby girl is fourth in line for the throne, after Prince Charles, Prince William and her elder brother George, who was born in July 2013.

Dozens of fans of Britain's royal family waited patiently outside the hospital in anticipation of the birth of the royal couple's second child. Draped in Union Jacks, they greeted the announcement with cheers. "There isn't one like our royal family. That's why people come here from all over the world," a fan from London said.

As the town crier announced the birth of the royal family's second child, fans remembered the time when Princess Diana gave birth to her two sons, Prince William and Prince Harry. "It's like a memory of princess Diana," one fan said.