Princess Beatrice, the granddaughter of Britain's Queen Elizabeth who married Edoardo Mapelli Mozzi last year, is expecting a baby, Buckingham Palace said.
The baby, the first for Beatrice, the eldest daughter of Prince Andrew and Sarah, Duchess of York, and her property developer husband, is due to be born this autumn.
"The queen has been informed and both families are delighted with the news," the Palace said in a statement.
The princess, the ninth-in-line to the throne, and her husband wed at Windsor Castle in July in a scaled-down private ceremony that took place without the usual pomp and fanfare that royal weddings usually attract because of Covid-19 restrictions.
The queen currently has 10 great-grandchildren, with two new royal arrivals this year - Beatrice's sister Eugenie had her first baby in February and Zara Tindall, the daughter of Princess Anne, gave birth to her third child in March.
Prince Harry and his wife Meghan are also expecting their second child this year.
The announcement of the pregnancy provides some good for the 95-year-old monarch whose husband of more than seven decades Prince Philip died last month.
In a further blow to the queen, one of two Dorgi puppies she was given by Prince Andrew to cheer her up after Philip fell ill in February died over the weekend.
"The queen is absolutely devastated," an unnamed royal aide told the Sun newspaper. "Everyone concerned is upset as this comes so soon after she lost her husband."