In the great battle between the Jasons, the winner is...Jason. Bet you didn't see that coming.
Luckily, it's our Jason we're talking about here. After reuniting with his family, Jason battles a horde of doppelgängers and successfully earns his spot as the father of the Dessen household. This is all cool, action-movie stuff, but the important part is that Daniela and Charlie actively choose who they want to end up with. That's key.
But there's still a problem—the Jasons. In a crazy move, our Jason decides to take the family into the multidimensional box so that they can find a new world where they can be safe. But that's not the most interesting part. This is:
"Yeah, but I'm not going to open a door, and neither are you."
I turn to Charlie.
He says, "Me? What if I mess up? What if I take us to some terrible place?"
"I trust you."
"I do too," Daniela says. (15.124-128)
What's happening here is that Jason is taking his hands off the wheel and allowing his son to chart the family's path. That's huge. Not only is this awesome because the Dessens could end up in any manner of crazy universe, but also because it represents a big moment in this father-son relationship.