My 12 week old is hard to get to sleep, and needs help, especially with naps. Sometimes I miss that golden moment when he will doze off, and he goes full circle and gets wide awake again and wants to play. What's the best thing to do? Carry on battling to get him to sleep, as I know he's tired really, or let him play, look around etc, and hope that he won't be too tired to sleep later?