My DS is 10 months and he figured out that he can stand in his crib. What used to be a relatively easy task, now takes me about an hour to get him to sleep and then I'm ready for bed too. As soon as he stands up, I lay him back down, but he thinks it's a game, he just rolls over and laughs. I've tried to be more assertive with my voice, but I'm not sure if it's working. I have a chair near his crib and sit in it after putting him back down. Anyone have any advice?