Swedish Crown Princess Victoria and her husband have gone into quarantine after testing positive for the coronavirus, the palace said on Thursday.
Both Victoria, 43, and her 47-year-old husband, Prince Daniel, have mild flu symptoms, but were doing well under the circumstances, the statement added.
The couple were tested on Wednesday, and were self-isolating with their children, Princess Estelle and Prince Oscar.
The royal family's physician has begun efforts to trace the chain of infection. Due to the infection, the couple were unable to attend a televised memorial service at Drottningholm Palace Chapel, just outside Stockholm, to mark the the one-year anniversary of the first Swedish death due to the pandemic.
King Carl XVI Gustaf and Queen Silvia were attended the service.
King and queen vaccinated
The king and queen were vaccinated earlier this year.
Victoria's brother, Prince Carl Philip - fourth in line to the throne - and his wife, Princess Sofia, tested positive in late November.
Carl Philip and Sofia substituted for the crown princess and her husband at Thursday's service.
In the early stages of the pandemic, the king and queen self-isolated at Stenhammar Palace, about 120 kilometres south-west of Stockholm. They returned to Stockholm in September.
The country of 10.3 million has recorded 13,111 corona-related deaths and 707,000 coronavirus cases since the pandemic began.
