This is just a curiousity quesiton to learn more things. My children finally got weighed and measured yesterday. They both just got radians. My son is 4 yrs 4 months old and weighs 39 lbs and is 41 3/8 inches, so of course he is FF but my daughter who is almost 22 months weighs 26 lbs 5oz and is 34 and half inches tall, we plan on putting her RF when we install the radians but my question is if the seat says rf untill 33 pounds is that regardless of height as well? Also why is there a weight limit on when/how long you can use the LATCH, isnt latch more safer than using a seatbelt?