Don't worry -- even if your baby is wailing all the time now, research shows that young babies who are fussy are not more likely to grow up grouchier than their peers. So what's behind all those tears?
• Some babies' central nervous systems are more sensitive and reactive to stimulation from the outside world. As they mature within the first four months, they usually become better able to handle the many sights and sounds they're rapidly encountering.
• If your infant spits up a lot, or regularly pulls away during feedings, often stretching and turning her neck, gastroesophageal reflux disease may be making her irritable. GERD is a complication of frequent reflux -- stomach acids backing up into the esophagus and sometimes out of the mouth. Talk to your baby's doctor if you suspect GERD.
• She may have colic -- continuous crying for more than three hours, three days a week, during the first three months. Although a definite cause is unknown, colic will go away and won't harm your baby's development or demeanor.
Whatever the cause of your child's crankiness, it's important to find ways for you both to cope. If nothing works to soothe her, put her down in a safe place for five to 10 minutes. She (and you!) may need a total break from stimulation -- the rocking, singing, and talking -- to calm down.
Originally published in American Baby magazine, November 2005. Updated 2009.