The 17-year-old actress, who stars as Hemsworth's on-screen lover in the romantic movie, said that they "grew into" a relationship.
Showbiz Spy quotes her as saying: "We had been filming for a couple of weeks and I think the more you hang out, the more you get to know each other - we kind of grew into it.
"We weren't [fully] a couple until the end of the film. We were hanging out and I guess we were kind of dating but there wasn't ever a moment where we thought, 'Yeah, we're together'."
The star added: "I got really lucky working with someone I enjoy being around. I'm super blessed to have had amazing people in my life.
"I think the best part is just hanging out with a friend and that's what him and I are - it's a real friendship. We've always been kind of what we are now."
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