The couple, who are now parents to son Camden Jack, have had a rocky romance in the past.
After initially calling off their engagement in July 2011, Cavallari and Cutler were back together by November of that year.
The 25-year-old reality star said that things weren't as romantic with the sportsman the second time around.
Cavallari told E! News: "It was so silly. I was in the airport, leaving Chicago.
"We had just spent however many days together and we were texting and somehow it came up, like 'Oh, shall we get married?' We're like, 'Yeah, okay.' "
Cavallari also added that Cutler didn't present her with an engagement ring in person, saying: "Then, he sent my ring in the mail. So I actually had my ring sitting at home for a couple of weeks before I put it on."
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