We have had 5 children, and of those, only one (the 4th) did the same thing--constant crying. But it would start around 4:30 p.m. and he wouldn't stop crying until the wee hrs. of the a.m., usually around 4 or 5 a.m. The doctors said he did not have colic or any physical problems, but that he was also probably frustrated. The dr. suggested strapping him into his car seat, placing him on the dryer, and turning the dryer on. It mimics the action of a car in motion, and lulls him to sleep or keeps him entertained by the steady thrum. Try it. -Sandy [Sew with 7]