Unlike me, a lot of child actors are very short, which is why they work. So when they're 15 they can play 11 or when they're 18 they can play 14. They look young for so long, they have abilities a much younger kid wouldn't have. ↗
When child actors act well they're just reacting to situations, and they're acting very real because their life experience is so short; there's no history to fall back on. ↗