This is a huge factor that non-parents don’t realize. Today’s car seats are huge, to the point that they’ve been seriously proposed as reducing family sizes. Mo

This is a huge factor that non-parents don’t realize. Today’s car seats are huge, to the point that they’ve been seriously proposed as reducing family sizes. More expensive car seats are even bigger, with anti-rebound bars, seat-to-floor bars, and extra side padding. We tell parents to keep their seats rear-facing as long as possible (in many circles up to the age of 4, with limited evidence), and discourage smaller booster seats. There’s no comparison between the situation today and a generation ago. And that’s just the car seats. Strollers are also huge (the latest trend is for newborns to lie flat in a bassinet, which is basically a mini-crib in a stroller). It all adds up, much faster than you would expect.