The problem with trying to split, the it must be the oldest child who is the boy or the youngest child who is the boy is that the two situations overlap. You need to split the situation into oldest, youngest and both. If we made the ruling that both should be excluded, then we’d be able to complete the argument that there shouldn’t be a difference between knowing that one child is a boy or knowing that the oldest child is a boy.
The problem with trying to split, the it must be the oldest child who is the boy or the youngest child who is the boy is that the two situations overlap. You need to split the situation into oldest, youngest and both. If we made the ruling that both should be excluded, then we’d be able to complete the argument that there shouldn’t be a difference between knowing that one child is a boy or knowing that the oldest child is a boy.