Sure, you can drive the car. It doesn't matter if you're registered or not. And because you are an insured driver, that makes it even better, even if you're not insured to drive that car.
Having the same insurance isn't the issue. The issue is whether or not your state follows a "family doctrine purpose", which covers anyone in the immeadiate family regardless of who is driving, or follows an "ownership statute", which extends the priveledge to anyone driving the car with permission of the insured owner.