“For someone on the outside, it might seem their engagement came too quickly,” a source tells PEOPLE. “But for everyone close to them, it feels like they have been dating much longer than they actually have.”
The couple hit it off after Schwarzenegger’s mother, Maria Shriver, introduced the two.
The insider adds, “They never had a typical relationship. It very much helped that Chris already knew Maria. They didn’t have to take things slowly because they were getting to know each other’s families. Katherine’s family instantly treated Chris like a family member.”
Pratt, 39, and Schwarzenegger, 29, spent New Year’s Eve in Mexico with her family. The vacation was just another example of how close Pratt had become to the tight-knit family.
The lovebirds have also recently moved in together, a source previously told PEOPLE.
“Since they started dating, Katherine has taken Chris to all of her favorite neighborhood places,” the insider said. “And Chris clearly likes her neighborhood.”
Pratt, who used to live in the Hollywood Hills with ex-wife Anna Faris, joined his fiancée in west Los Angeles.
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The actor kept things traditional by asking Shriver and Arnold for their daughter’s hand in marriage, a source previously told PEOPLE.
The question came as no surprise to her parents, the source said, as Pratt has long been vocal about his desire to start a future with Schwarzenegger.
“Chris has been very straightforward about his intentions from the beginning,” the source said. “Over the last few months, he’s been bonding with all of Katherine’s siblings and it was clear to her entire family they would get married.”
For more about Pratt and Schwarzenegger, pick up this week’s issue of PEOPLE, on newsstands now.