Lindsay Lohan was shocked by Egor Tarabasov's proposal.
The 29-year-old actress was taken by surprise when the Russian businessman popped the question last weekend after just seven months of dating because she hadn't seen it coming.
A source said: "She didn't see it coming."
A few days after the proposal, the couple were seen at a Duran Duran concert with Lindsay's parents Michael and Dina Lohan, and the insider told the publication Egor had initially planned to propose when they were all together in New York, but didn't explain why he changed his plans.
The real estate agent presented the 'Mean Girls' actress with a five-carat oval emerald ring, which the actress had seen at an auction a few days before.
The source told the New York Post newspaper's Page Six column:
"She was saying how much she loved it and he went back and secretly got it."
Lindsay's mother has given her daughter's relationship her seal of approval.
She said recently: "He's just a sweetheart He's an only child and I just FaceTimed with them and his mom a few days ago. He's cool and he's very mature for his age.
"He's older than his years. Being an only child and travelling the world educates you in other ways. He's not about celebrity or anything, which is really important."
And her dad Michael is also a fan of Egor.
He said last month: "He has a lot of strong connections in Russia -- these are big people and they're very supportive.
"He wants things to be in the right place for Lindsay and he's wise beyond his years."
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