Inconsolable crying - a normal phase in infant development - is the most common trigger for Shaken Baby Syndrome, the result of violent shaking that leads to a brain injury. Infants are at greatest risk because they cry longer and more frequently, and are easier to shake than older, larger children.
Parents and caregivers, know this: You may not be able to calm your baby. That's not your fault, nor your baby's. It is normal for healthy babies to cry much more in the first four months of life. Think of this as the "period of purple crying." Purple stands for:
P - Peak pattern. Crying peaks around 2 months, then decreases.
U - Unpredictable. Crying for long periods can come and go for no reason.
R - Resistance to soothing. The baby may keep crying for long periods.
P - Pain-like look on face.
L - Long bouts of crying, which can go on for hours.
E - Evening crying. Babies may cry more in the afternoon and evening.
Sources: Department of Health and Human Services and the Centers for Disease Control and Prevention