They was first spotted at a filmmaker event in Los Angeles in November — and they've been inseparable ever since!
"Lorraine made the first move," an insider told RadarOnline.com.
"She's quite an intense character who knows what she wants, while he's a bad boy like his dad. They're perfect together!"
The sources said the relationship is "pretty serious and well known among their close friends."
Added the spy: "They've known each other virtually their whole lives … but things only got romantic around six months ago."
Their parents approve — even if Jack is keen to keep an eagle eye on them!
Since Hopper still lives at home, "Sean is pretty encouraging," said the source.
"On the other hand, Lorraine has a house in L.A., and they hang out there a lot, so Jack's a little more cautious!"
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