See The (Dangerous) History Of Kids In Cars
When I was a little kid, around kindergarten age, my sister and I sat in the pop-up seats in the back of our old station wagon. There were two little bench seats and we faced each other. We called it "The Backie Back," because it was even father back than the back seat. It did not have any seatbelt of any kind.
Any time I wanted to go up and visit mom, all I had to do was climb up over the middle seat, into the front seat, and plop myself down between mom and dad. There was plenty of room. At no time were my parents in any danger from being pulled over for child endangerment.
But over time people began to see the need for restraints. At first no thought was given to what would happen if there was a wreck. The idea was to keep the kid from becoming a problem for the driver. That is why this simple leash system was invented (see here) to allow the kid to get up and move around but to also keep him in the back.
The first actual seat was a step in the right direction, but still pathetic. As this newspaper ad shows, it's just a metal frame with a hammock for the butt.
Later models, like this one, offered a trey to feed the kid or provide a place to bang toys around. More padding and restraints were added, like in this model, but nothing that would actually protect the kid.
Want to see a really scary one? This model did not even buckle in. It just hooked over the seat. All it really did was provide the kid with a view outside. There is no way it could actually protect a child from flying, seat and all, across the cab. Actually, I think my mom had this model for me, it came with a steering wheel so I could 'help' drive.
Here is an add for a Lull-A-Baby Car Hammock. Probably great for rocking the baby to sleep but it might just be the least safe invention yet. At least this version of a baby bed had the kid on the back seat. I remember honking that red horn at other cars.
We've come a long way. Wonder how we survived.