The Irish comedian revealed all while appearing on ITV's Loose Women, telling the panel how he travelled across the pond just to surprise Cat on her birthday.
The pair had been close friends for years, but hoping to take their relationship beyond friendship, Patrick made a last minute trip to LA and joked: "[Cat] fell off her chair and we've been together ever since."
Ruth Langsford had asked if there was a moment that saw the pair become an official item.
He told her: "There was a moment... it was her birthday. She was in LA... obviously LA is eight hours behind, so I text her happy birthday from a little Irish pub. It was about 2 o'clock in the morning, near closing time. She said it's just a shame you're not in LA, I'm having a lunch tomorrow and I said I'll be there.
"So I got up at five, jumped on a six o'clock flight from Ireland, got into Heathrow at seven, jumped on a twenty to ten flight, got in at quarter past one and walked into the Beverley Hills hotel. She fell off her chair and we've been together ever since.
"There was a brilliant moment where I was speaking to the taxi driver, I was in the taxi to the hotel and he pulled up and said, 'Sir would you like me to wait for you'."
Luckily he didn't need to! Cute, right?
A year later the pair then tied the knot in a romantic ceremony in Rome. They married on 30 September 2012.
Fast forward three years and Patrick and Cat are now expecting their first child together. The couple announced their exciting baby news back in September via Twitter.
Cat tweeted: "Exciting news.... Paddy and I are so happy to be expecting our first child in the Spring..... Lucky us."
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