All children are different, but this is a ride that is meant to scare the daylights out of you. Have you been on TOT? If so, and you know your child can handle it, then go for it. The poster above is correct... be absolutely honest and let your kid decide.
If you've never been on it, then ride it first. If you can't ride it without your child, I'd skip it and save it for another trip.
By the way, TOT is one of my absolutely favorite rides. If you haven't experienced it, you don't know what you're missing!