Our 5 1/2 month old refuses to nap for any longer than 15 minutes. 20 if we're lucky. No matter what we try he will not sleep any longer. We have tried letting him cry it out but he won't stop crying until hes picked up or he'll just play in the crib until he screams. He is still waking up every 3-4 hours a night to eat and will not calm down at night or go back to sleep until he eats. He recently, the past couple weeks, has been waking up at about 4am and staying up screaming until 5am. We dont know what to do anymore and his pediatrician just told us to let him cry for 15 minutes and then get him. We told her we have done this but she hasn't given us any other advice.