Secret chemistry set trick for onion carmelization: a TINY pinch of baking soda in the pan as you’re cooking them. Put too much in and you’ve got onion mush, but just a tiny bit and the onions soften as if by magic.

Diono Radian RXT. I’ve had 3 of those in the back seat of an Outback. Works fine. (they were all forward facing at that point. Would not recommend for rear facing because they’re super long.