Es head is starting to poke over her car seat. I'm thinking reluctantly that its time to move on to the next stage. She's 100cm and weighs 15.5kg so it's safe for her to have a high back booster isn't it?! Can anyone recommend one? I want one that still has the harness, especially over here as the roads are terrifying and prefer isofix but its not essential. I'll have to order in the uk to collect next month as there's very little choice over here.