'No surprise' Philip occasionally cancels engagements
The Queen's eldest grandchild Peter Phillips said it "should not come as a surprise" that his grandparents were occasionally forced to cancel engagements given their age.
The Duke of Edinburgh, 91, withdrew from an official engagement after falling unwell on the eve of a service to mark the Queen's 60 years on the throne.
Peter told Daybreak: "You've got to remember his age, both of their ages. Still what they do at their age, they do a lot more than most other pensioners of their equivalent age.
"If occasionally there is the odd engagement cancelled it shouldn't come as such a surprise given the work that they do have."
He also said that the service to mark the coronation at Westminster Abbey was "fantastic".