LOL TRUTH. And tbf we've all seen what happens when you cast kids and know how it has to shift for that. If you don't have a plan than LOST happens and you're like oh fuck have to write the kid off. I'm sure this is something they have considered. Especially with in this season him learning more about how to "slowly" move through time rather than jumping entire decades. Maybe he just experiments on himself and ages to 18. easy peasy.