HA! I have one of these! I left my 4yo DS with my mother today crying because I threw out his old carseat last night. The carseat that he has not used in over 6 months.
My DD6 has always had a "bring it on" kind of personality. She'll tackle any task or activity. DS just told me that soccer was "too hard" on Saturday.
You know, you think you've got one kid figured out and the next one throws you for a loop!
I am definitely going to start trying some of the ideas here. The other thing I am going to keep doing is to not coddle him. If a carseat/whatever needs to go, it needs to go. It will be done in broad daylight with little apology and just enough explanation.
SO glad I'm not the only one!