We, too, have a daughter who is waking up at the 45 min. mark not crying in a fussy way but screaming as if in sheer agony. We do not know the cause; we are looking into possible allergy issues. We also are struggling with the top teeth (dd is seven and a half months) which is likely exasperating the problem. Tonight was really tough; she did not go down until 10:25 and then was up screaming from 11:40-12:45. I have to head to bed (morning will be here much too soon), but if anyone has ideas they would be very appreciated.