King Charles spoke of his mother as a source of inspiration on Monday, during his first Commonwealth Day celebration following his installation, at a service in Westminster Abbey in London. He was joined by prominent members of the British royal family. Charles succeeded his mother, Queen Elizabeth, as the head of the assembly, which comprises 56 countries that were part of the British Empire, after her passing in September at the age of 96. The king (74 years old) was accompanied by his wife Camilla, his eldest son Prince William, and his wife Kate.