The event, in partnership with the Royal British Legion charity, was held at the palace's Orangery, just a few hundred yards from where Prince William and Princess Kate live with their children Prince George, 5, Princess Charlotte, 3, and Prince Louis, 7 months.
The Duke and Duchess of Cambridge found themselves in a snowball fight as they hosted more than 200 wives, girlfriends, parents and grandparents separated from loved ones over Christmas. And so do your families, some of whom we had the chance to meet yesterday at a party at Kensington Palace.
She said she had some idea how the relatives felt at this time of year as William, a former RAF search and rescue helicopter pilot, had served in the Falklands for six weeks in 2012.
She said: 'But I can't imagine how it feels when your loved ones are away on active service over Christmas or at those special family moments.
"But as we approach Christmas, Catherine and I feel strongly that praise for your work and recognition of your sacrifices is exactly what is due to you all".
She was hit with a mock snowball, but it was all in good spirits.
As artificial snow fell the two exchanged snowballs and Kate even found herself the target of a playful attack. The 92-year-old monarch looked her typical elegant self in the glittering gown, which featured delicate floral patterns and tiers of lace.
They met personnel from 11 and 31 Squadrons, operating Typhoon and Tornado aircraft, who have been flying missions in support of Operation SHADER, the UK's contribution to the ongoing campaign against Isis in Syria and Iraq.
Much has been made of how Kate and Prince William's roles have been changing behind the scenes as they prepare for Prince Charles to ascend the throne - they played supporting roles in most of his 70th birthday coverage and will be separating their courts from Prince Harry and Meghan Markle next year as both couples prepare for a future more independent of one another - but no moreso than their required attendance at certain events, and a strict dress code expected. "Or maybe that should be flexitarian", she said. "Did they get back [home] okay?"
He said about William and Kate: "For them to come out here and recognise the service, it goes to show that the work the men and women are doing is still valued".