Does anyone know how much a puppy should be sleeping? Max is 4 months old now. He usually sleeps about 9-12 hours through the night depending on how active he was in the day. There are a lot of periods during the day when he gets crabby and mouthy. I think it's because he's tired but he doesn't nap very well, even if I put him in his kennel. Should he be sleeping more during the day or is he just a mouthy little brat?