car seats...
oh dear, buffy thats a horrible thing to happen. but i have also heard such things before.
suggestions => i try to entertain them in their car seat, using cheap stickers, even scotch tape (babies like sticky stuff), books, pencils, stories, sing songs with actions, botles with caps and whatnots. just distract them when they cry. prepare something that u only play when they in the car seat, so that its a novelty and incentive for them.
or how abt getting some car seat toys, theres lots on the market, some are interactive ones where the baby holds a wheel and controls the animals and sounds on the big pad attached to the front seat, forgot the name. some is kicking toy where baby kicks and recieves response from the toy attached to seat in front.
when the kid is bigger, u can even make a show of asking him to show you how to put on the seat belt coz u forgot how to, and praise him like crazy once he does it. or play game to see who puts on the seatbelt or gets onto the car seat the fastest will win a prize. or nominate her/him to be the one to check if everyone is belted up safely, makes him feel responsible for it. but i think these things when they older and can understand. my son helps us put on his seatbelt. and he reminds me to put on mine when i forgot.