Queen Elizabeth celebrated the latest addition to her family with a quick horseback ride through the grounds of Windsor Castle.
The monarch, 92, was photographed enjoying her ride in Berkshire, west of London, after her grandson Prince William and his wife, Kate Middleton, welcomed their third child together — a son — Monday morning.
Her Majesty was joined by the palace’s head groom, Terry Pendry.
The arrival of the youngest member of the family comes just two days after the Queen’s birthday which was celebrated with a televised concert at London’s Royal Albert Hall.
While proud parents William and Kate have yet to reveal their son’s name, they did look overjoyed at their new baby while presenting him to a crowd of cheering fans outside of the Lindo Wing at St. Mary’s Hospital.
“Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 1101hrs,” a statement by Kensington Palace said. “The baby weighs 8lbs 7oz. The Duke of Cambridge was present for the birth.”
- Can’t get enough of PEOPLE’s Royals coverage? Sign up for our newsletter to get the latest updates on Kate Middleton, Meghan Markle and more!
“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,” the statement continued. “Her Royal Highness and her child are both doing well.”
The name of the baby boy will be announced in due course, the palace said. Albert and Arthur are tied as the most popular names for a boy – at 5-1 and 9-1, respectively, according to British oddsmakers.
RELATED VIDEO: Royal Baby No. 3 Has Arrived!
While William, 35, and Kate, 36, didn’t answer questions from the media after debuting their newborn son, the proud dad of three told onlookers that they were “very happy, delighted” about their new addition as he secured his son into his car seat.
Holding up three fingers, William smiled and said, “Thrice worry now.”
“We didn’t keep you waiting too long,” he joked about their quick hospital stay.
For the first time in history, a female royal’s spot in line to the throne won’t be bumped by the arrival of a younger brother. Thanks to the Succession to the Crown Act 2013, birth order determines who will become the next king or queen of the U.K., regardless of gender. Had it not been in place, Charlotte would have lost her spot when Kate gave birth to a boy.
The royal baby remains fifth in line of succession after Prince Charles, Prince William, Prince George and Princess Charlotte.
With his arrival, Prince Harry is now sixth in line, and Prince Andrew, Princess Beatrice and Princess Eugenie will all move down a place in the line of succession with the arrival of William and Kate’s younger son.