Car seat question

[Cheaptrick]

Hi

My 2.5 yo is on the 75th centile for hight and weight. He is very skinny and tall and weights 15kg at the moment and is 97cm tall. Our maxi car seat has a max weight limit of 18kg. But my son is already on the last slot for the seat belt and his head is over the top of the seat just. The car seat is ment to last till he is 4

He will out grow the car seat before he is 4 yo and because he is skinny the next range up does not hold him securely. Do i have to get a new car seat when his head is over the top of the seat or when he reaches the max weight?

Does anyone else have this problem? If you do what car seat do you have?

I had this with my child she was in a tobi (maxi cosy) She was almost 15kg but I wasn't happy with her being in a high back booster so I shopped around until I found one that had a higher back. Ended up with a britax duo. Shop thought I was mad said she would grow out of it in a few mths. She was in it intil she was 4. I now know about the britax two way elite. If I had known about it then and it fitted in the car I would have bought it.
Your other option is a high back booster with a impact shield like this one.
jane
mamas and papas also do them

we have had the same problem at 2.5yo with 2 of our dc's. we bought a britax evolva 1-2-3 for our dd,it was a fab seat,you use the harness until they are 18kgs, theres also the recaro young sport which is pretty good,otherwise theres the kiddy ones with the impact shield or the cybex pallas,
all of these type keep lo's harnesses (or using an impact cushion) until 18kgs,then the seat becomes a high backed booster until they are 11yo-ish :)