Because of cancer: King Charles isolated at Easter service. Only Queen Camilla is allowed to sit next to the monarch - he is isolated from the rest of the community for security reasons.
Not all British royals have been announced for the Easter Sunday service: it was announced in advance that Prince William and his wife Kate would not take part in the event. Her children Prince George (10), Princess Charlotte (8) and Prince Louis (5) will also not be present. This year the event will supposedly take place with a greatly reduced crowd out of concern for the king.