Getting around (Bangkok)

It looks like me, my husband and two children will be moving to bangkok in august. I am wondering how people get around the city with small children. It has been a long time since I was last in Bangkok and it was without children, but I don't seem to remember seeing carseats. I obviously noticed that the local kids are happy to hang off the back of a motorbike or lorry from a very early age!!! How does it work with taxis or do ex pats drive? Can you get car seats? I assume buses might be the best bet and walking.

Thank you in advance Jo x