DS is 2.8 and has always been a fairly good sleeper. Lately he has been waking in the middle of the night, crying and distressed. He's done it on and off for a few months, but lately it seems to be a bit worse when it happens. Sometimes he settles down with a back rub, sometimes he cries so much and seems to be in pain that I give him 5ml of Calpol which generally settles him again. Other than this, he doesn't show any signs of being ill during the day, and it doesn't happen every night, just 2-3 times a week. Has anyone else had this happen? Any ideas?