WATCH: Downcast Queen arrives at church ahead of emergency meeting with Prince Harry
According to the UK's Daily Express, the Queen attended the Sunday service at St Mary Magdalene Church alongside Peter Phillips, the Queen's eldest grandson, and the son of Princess Anne.
Top royal reveals how Queen Elizabeth II is doing amid Prince Harry and Meghan Markle drama
When asked how the Queen was doing, he said she was "alright".
Prince Charles is expected to attend the meeting alongside his sons with Prince William and Prince Harry. Meghan is said to be phoning in from the UK where she is currently residing with their son Archie.
It will be the first meeting since Prince Harry and Meghan announced that they intended to step down as "senior royals".
It is thought that Meghan and Harry made their announcement on January 6 without the Queen's consent or her knowledge.
Meghan and Harry
A royal source told The Daily Telegraph: "The family will gather on Monday at Sandringham to talk things through, attended by Her Majesty, the Prince of Wales, the Duke of Cambridge and the Duke of Sussex.
"Following a series of meetings and consultations across the last few days, there are a range of possibilities for the family to review which take into account the thinking the Sussexes outlined earlier in the week."