Queen Elizabeth is 'delighted' as Prince William and Kate Middleton welcome their little Prince

Prince Williamand Kate Middleton now have a party of five – and Queen Elizabeth II and the royal family are "delighted"! The royal couple welcomed their third child, a baby boy, on the morning of April 23, with Kensington Palace announcing: "Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 1101hrs. The baby weighs 8lbs 7oz. The Duke of Cambridge was present for the birth. Her Royal Highness and her child are both doing well." Like the newborn's older siblings, Prince George and Princess Charlotte, William and Kate's third baby was born at the Lindo Wing at London's St. Mary's Hospital.

Not long after, it was revealed that the Royal Family had been notified, and were "delighted" about the new arrival. "The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, Prince Harry and members of both families have been informed and are delighted with the news," read the statement from Kensington Palace.

William and Kate now have a son, joining Prince George and Princess Charlotte. Photo: Getty Images

A name for the tot has yet to be revealed, but is likely to be announced in the coming hours. Catherine and William are also expected to pose with their new arrival on the steps outside the Lindo Wing, as is royal tradition.

PHOTOS: LOOK BACK AT GEORGE AND CHARLOTTE'S DEBUTS AT THE LINDO WING

Kensington Palace announced last September that the 36-year-old was pregnant. "Their Royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child," the palace said in a statement. As with her previous pregnancies, Kate suffered from acute morning sickness, also known as Hyperemesis Gravidarum, forcing her this time around to miss her son's first day of school at Thomas’s Battersea.

William and Kate are seen here introducing Princess Charlotte outside the Lindo Wing after her birth

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Kate hinted last July during her royal tour of Poland that she had babies on her mind. During a visit to Warsaw’s The Heart, an incubator for digital and tech start-ups, the mom-of-three joked that she and William should have more children. “We will just have to have more babies,” she said.

In February, the Duchess revealed that her husband was "in denial" over becoming a dad-of-three. That same month, William joked about his wife expecting twins. "Twins? I think my mental health would be tested with twins," he said. "Two is fine, I don't know how I'm going to cope with three, I'm going to be permanently tired."

With their third child, who is now fifth-in-line to the throne, Prince William and the Duchess have broken royal tradition and have become the first royal couple – in the Queen's immediate family – in 58 years to have more than two children. Queen Elizabeth herself has four children – Prince Charles, Princess Anne, Prince Andrew and Prince Edward, all of whom have kept with the tradition of having two children each.

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