The cold also caused the Duchess also cancelled an appearance at the Olympia Horse Show on Wednesday evening.
While the duchess was recovering at home, the rest of the royal family were out in force.
Prince William and Kate were spotted in their car with their two eldest children, Prince George and Charlotte and they were accompanied by their nanny Maria Turrion Borrallo. Prince Harry and Meghan arrived in a separate car.
Also, in attendance were Prince Andrew, Princess Beatrice, Mike and Zara Tindal and Sophie, the Countess of Wessex.
The luncheon is an annual tradition that is hosted by The Queen mid-week in the seven days before Christmas.
The lunch provides The Queen with the opportunity to spend time with members of the extended family, who will not join her for Christmas in Sandringham.
