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You can get a high back booster that still has a 5-point harness.
You could also try a neck pillow and see if that will keep his head/neck from falling which might be causing the rest of his body to bend.
My 5 year old moved to a high back booster seat but he usually falls asleep as we ride and ends up bend over, this worries me in case some accident or sudden braking. Is there another option or something I can add to secure his upper body, seatbelt isn't enough..
I purchased a 5 point harness seat but for some reason it's the same problem....not as much as half his body but his head hangs, thanks for the responses, looking to exchange seat and try a few others.
You can get a high back booster that still has a 5-point harness.
You could also try a neck pillow and see if that will keep his head/neck from falling which might be causing the rest of his body to bend.
A 5 point harness is really your only option.
Lean his seat back slightly. When he falls asleep his head will roll to the left or the right but still be touching the seat.
In Oklahoma kids go out of car seats at 6 if they're big enough so our kids were in boosters at 3. If you're in a wreck he has the same protection you do with this seat belt across his chest.
I agree with the five-point harness. Our six year old still hasn't outgrown the height/weight limit of the Britax he got when he was 1.5 or so, so we are keeping him in it. He's not wild about it, but it's the safest option and it's not like his friends see him in it. (we walk to/from school, so no embarrassment)
A five point harness is safest for anyone who fits properly in it. It is certainly worth investing in one that will fit him for a few more years. My 11 year old daughter (tall and skinny) just outgrew the harness in the britax frontier a few months ago. She always falls asleep in the car and now hates how uncomfortable she is in a booster seat. Children's bodies are not like an adult's. Even when a seatbelt is positioned properly, it still puts more stress on a child's more fragile bones and organs. A five point harness not only ensures a better/tighter fit when used correctly, but it also reduces the force on their bodies. Also, just because it is legal to move to a booster doesn't mean it is safe.
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A five point harness is safest for anyone who fits properly in it. It is certainly worth investing in one that will fit him for a few more years. My 11 year old daughter (tall and skinny) just outgrew the harness in the britax frontier a few months ago. She always falls asleep in the car and now hates how uncomfortable she is in a booster seat. Children's bodies are not like an adult's. Even when a seatbelt is positioned properly, it still puts more stress on a child's more fragile bones and organs. A five point harness not only ensures a better/tighter fit when used correctly, but it also reduces the force on their bodies. Also, just because it is legal to move to a booster doesn't mean it is safe.
It sounds like he should still be in a five point harness. That will keep him secure and prevent the slumping when he falls asleep. Look into the Britax Frontier or the Graco Nautilus - both have high height and weight limits and can convert to a high or low back booster when your son is ready. From what you said, I really don't think he's ready to be in a booster seat and he will be much safer if he's harnessed.
ETA: My son is six and still sits in a 5-point harness most of the time. Many of his friends do, though some now use only boosters. Last week, we were on vacation and had him only in a low back booster. He fell asleep a couple of times in the car and was slumped over so much it looked really uncomfortable and unsafe.
All of my kids were in the 5 point until age 6 then a booster until age 8 (longer if they couldn't see out of the windows LOL). Keeping your child's head back is a battle every parent has fought without winning.
Do you lock the seat belt when he buckles in? Sometimes buying another car seat isn't an option, especially if you have a taller child. If you pull the seat belt out and lock it back, a lot like when you strap in a car seat, it might give him the added support of keeping him from being slumped over. Make sure the shoulder strap lays properly across his chest, if not adjust the back of the booster until it does. That might help.
Harness for sure, in that case.
In a wreck he has much more protection than you do in a seatbelt. There are sides to the seat (some offer a good deal of side protection, more than others). There are "artificial hips." The booster makes sure the belt fits over the strong parts of his body. Make sure you use the booster until he actually fits the adult belt, which is age 11 for the average child. Otherwise the lap belt rides high near the stomach. In an accident, that's a serious or fatal internal injury.