Fontanelle is the soft spot on a baby's skull. It allows the baby's head to squish during childbirth. Fontanelle disappears naturally, but can be helped by rubbing in vitamin E, sulfur, or sticky substances. In some cultures, fontanelle was viewed as an eye through which the outside world could enter the baby's brain and give it knowledge. See: trepanation.
Bulging or swollen fontanelles have been linked with many vaccines commonly given to infants, such as the diptheria-tetanus (DPT) vaccine. Many families, out of concern for their child's health, have sought legal justice for the potential health damage.