Ferber method founder Richard Ferber, Director of the Center for Pediatric Sleep Disorders at Children's Hospital Boston, concurs with "Baby Wise" regarding some of its sleep advice, but he warns against expecting too much. "Baby Wise" predicts that the 8-week-old child will be sleeping 7 to 8 hours in a row at night, and the 13-week-old child increasing the nighttime sleep period to as much as 11 hours. Ferber said, "Parents shouldn't expect babies to sleep that long that early, although a very few will on their own" and says that the book may frustrate parents of babies that are not sleeping so much; the parents may wonder what is wrong with the infant. Ferber says that if a baby sleeps through the night, the parents may actually need to wake it for feeding.