Parents receive lots of child-rearing advice, including, “spare the rod and spoil the child.” But researchers from the Johns Hopkins Bloomberg School of Public Health have discovered that children who are spanked before the age of 2 are more likely to have behavioral problems years later when they enter grade school. “Spanking children under the age of 2 puts those children into a higher risk group for behavioral problems later,” says Eric P. Slade, assistant professor at...