It's not reinforcement learning, because the child can do it the first time, so there's no reinforcement. I have kids, so many times I have played games with them successfully, purely from a description of the rules and playing as we went. They even beat me once the first time we ever played a game, by employing a rule at the end which had never come up in previous play. Compared to that Alphago isn't even in the race, because we can't even tell it the rules.