Paddy Kelly, 70, was due to fly at 12.20pm today to Belfast International Airport to spend Christmas with her family in Castlederg in County Tyrone, Northern Ireland, and see her great-grandson Theo Hackett for the first time after he was born on November 16.
But she will be spending Christmas with her cat after Gatwick Airport's runway was closed last night due to two drones flying over the perimeter fence.
Live blog: Everything we know so far about the Gatwick Airport drone disruptionGatwick chaos: Your rights if your flight is delayedGatwick Airport staff praised after drones cause travel chaosShe said she was 'absolutely gutted' to be missing Theo's first Christmas. She said: "I was looking forward to seeing my grandchildren too, but especially Theo, because they change so quickly at that age. You want to see them as soon as possible.
"I'm stuck in Hove this Christmas, and I'm not a happy bunny."
Paddy, from Tisbury Road, Hove, was due to get a coach from Pool Valley in Brighton this morning, but her daughter, who booked the flight, was contacted by Easyjet at around 8am to say that the flight was cancelled and for her mother not to travel - meaning her £28 coach ticket was also wasted.
They were given the option of a refund or to rebook, but the earliest flights they could get were January 3 or 4.
The disruption started at around 9pm last night, when the two drones were sighted. According to the BBC, the runway was reopened at 3am, but closed again about 45 minutes later after another drone was sighted.
The airport said another drone had been spotted at around midday, and would not open until 4pm at the earliest.
Sussex Police confirmed the drone disruption was being treated as deliberate, but not as a terrorist attack.To them, Paddy said: "I just think they are the lowest of the low - not just ruining my holiday, but everyone else's. It is so inconsiderate. When people do things like this, they should be locked up."