A heavily pregnant Kate refused to be put off by bitter wind and snow as she joined Prince William to celebrate St Patrick's Day with the Irish Guards.
The Duchess of Cambridge showed no sign of feeling the chill as she smiled and chatted with members of the 1st Battalion at their base in Hounslow, west London.
She and the Prince watched the traditional St Patrick's Day parade before presenting troops - and their Irish Wolfhound mascot - with the shamrock.
Kate, who is due to give birth to the couple's third child next month, wore a green Catherine Walker coat and a Gina Foster hat to ceremony.
Some 350 soldiers arrived on the Parade Square in their red regalia, led by Irish wolfhound Domhnall.
William took the salute as the regiment continued a march-past and three thunderous cheers were then declared to the royals.
Earlier, Domhnall's handler, Drummer Aidan Cathcart, jokingly expressed reservations that his charge would behave.
He said: "Domhnall's role is very monumental - he is the first guy on the parade. He is the main guy on the march, it's a pretty important day for him."
Asked if he was confident Domhnall would perform as planned, he replied, bluntly: "No."
The wolfhound - the regiment's longest serving mascot since 1985 - had been doing test runs all week to prepare for his moment in front of the royals.
It is the fifth time he has received the shamrock and the second time he has been handled by Drummer Cathcart.
The Irish Guards were well prepared for the surprise turn in the weather, having recently conducted the Changing of the Guard in heavy snow during Storm Emma.
Also among the guests on Saturday was the Irish Defence Force's most senior military officer, chief of staff Mark Mellett.