car seat harness height

car seat question for toddler?

I bought a couple new carseats since my toddler is a big boy and outgrowing his. He meets the weight requirements, but needs to grow 1 more inch before he meets the height requirements. However, he is almost two and these carseats do not have the shoulder straps (only the lap belt) and I’m assuming that the seatbelt in the backseat can be used over the shoulder. I can’t find any info on what age the child should be before they should stop using the 5 point harness. Can anyone help?
20 months old, 35 pounds, and 33 or 34 inches tall. He’s a big boy! So what happens if he outgrows a convertible seat before the age of 4? What shall I do then!!!!
I bought a high back booster seat that only has a lap belt, not the 5 point harness. I didn’t realize it didn’t have that until after I bought it, now I’m just wondering when I can use it.

Ask your doctor. My son has been in a booster with a regular seat belt for a year now and STILL doesn’t meet the weight requirement. The doc said he was enough over the height and close enough to weight that it was perfectly okay. He’s 4 now. And my nephew was cleared by the doc to sit in one when he was two. But if he’s only an inch shy, I would think it would be fine. Definitely check with the doctor though

BTW we use the backless booster. Different ones have different weight and height requirements though they are all close.

New seatbelt laws go into effect
Booster seatbelt law to be tough on enforcers, as well as  citizens. Required full compliance will become live and expensive June 1