2 days ago my 10 month old son, just started hating to go to bed. He now cry's constantly. We've checked that his diaper is dry, he's eaten plenty, and even acts extremely tired. (slouching head, doesn't want to play, doesn't want to stand up, etc.) So we are pretty convinced that he is really tired, there is nothing wrong, etc. But we put him down, and he cry's and cry's. Today he cried for about an hour, and then eventually went to sleep. Is this bad? How long should we let him cry it out? He's obviously really tired, and we feel we may just be giving in to his desire for attention if we pick him up. But how long is too long to let him 'cry it out'? Thank you!