The law says no but you alone can tell if she is ok without it My dds are 7yo and this will be the first time that I won't bring their seats. I know many will say that I'm insane but it's a choice that I made. travelling with 4 kids on my own should be interesting and I have to bring 1 car seat for the baby, 3 booster more would be too much for this mama although I already thought of putting them all in a suitcase LOL