Queen Elizabeth is under medical supervision at Balmoral. Buckingham Palace released a statement on Sept. 8 revealing that doctors are concerned about the 96-year-old monarch’s health.

“Following further evaluation this morning, The Queen’s doctors are concerned for Her Majesty’s health and have recommended she remain under medical supervision,” the statement reads.

The palace added, “The Queen remains comfortable and at Balmoral.”

Both Prince Charles, who is first in line to the throne, and Prince William traveled to Balmoral. The Duchess of Cambridge reportedly did not join her husband because today is Prince George, Princess Charlotte and Prince Louis’ first day of school at Lambrook. According to HOLA! USA’s sister brand HELLO! , it’s been confirmed that the Queen’s three other children, Princess Anne, Prince Andrew and Prince Edward, are also with the monarch.

Her Majesty was pictured earlier this week with the UK’s new Prime Minister Liz Truss at Balmoral Castle. Following the palace’s statement on Thursday, the prime minister tweeted, “ The whole country will be deeply concerned by the news from Buckingham Palace this lunchtime.”

Liz continued, “My thoughts - and the thoughts of people across our United Kingdom - are with Her Majesty The Queen and her family at this time.”