The moment was a little out of character for Sophie, who told 9Honey that normally she would "never" approach, let alone kiss, a fellow passenger during a flight.
But, it was the unique "chemistry" that Sophie said she had never felt before with anyone that drew her in.
“I just sat down and he had a sense of humour and I was like, ‘Oh how relieving, sitting next to someone you can have a chat with',” she said.
“I was like, ‘Good sense of humour, hard worker’… it just happened.”
Sure enough, the chemistry between them held strong, and Sophie even described her relationship with Joshua as "the best" and that she can't wait to be married to him.
In a chat with TV WEEK, the blonde beauty confessed: "I've never had someone move in with me – ever. I love it. I wake up, he gets me coffee… It's so nice having him there. He's perfect."
She also gushed about her beau, saying he is "awesome", and the two of them are "really good".
"I definitely feel more comfortable and more myself with him than in any other relationship."
And three years after their chance meeting, Joshua finally popped the question, with Sophie taking to instagram to announce their engagement on January 15, 2021.
"Told you I’d tell you guys first💍🙌 I’m engaged. I honestly can’t thank you enough for all the love and support," she penned.
"@joshuargross and I are so happy. Josh designed a very personal ring with my favourite Aussie designer @luke_rose_jewellery and I LOVE IT."
The pair hosted their engagement party a few months later, with Sophie taking a moment to express how "lucky" she felt.
"This is our engagement party at home. I feel very lucky ❤️@joshuargross I love you so so much. 😍Thank you for putting up with me 😜 and cleaning up after the party."
Joshua also took to Instagram to gush about his fiancee, and wrote: "Luckiest man alive... xxx ❤️@sophiemonk."
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