My neighbor puts her 3 year old and her now 5 year old on a bus every morning to go to their summer school program. Well she tells me that on the bus the kids use the shield boosters without a back and just the lap belt. Her 3 year old is teh same size as my 18 month old too and her 5 year old is smaller than my DS (40 lbs, 42"). I didn't think those boosters were used anymore, let alone on a school bus. Now she thinks she should put her three kids in those for her van and car You don't even want to know what these kids are restrained in right now..or rather barely restrained in.