Girls. Baby is 3-3.5 hours not sleeping. Day and night. In our age 1-1.20…

Girls. Baby is 3-3.5 hours not sleeping. Day and night. In our age 1-1.20 not sleep normal. And 3-4 hours this over. And crying and not crying just lying down, and sometimes belly hurts, but not all the time, but if falls asleep on hands, then only in bed you put it up wakes up, and so only through 4 hours falls asleep. What could be the reason?