Children need special attention when traveling in passenger cars and trucks. Their skulls are more fragile, necks are thinner, bodies are shorter and heads are proportionately larger. Motor vehicle crashes are a leading cause of death and injury for children. Every year approximately 500 children between the ages of 4 to 7 are killed in motor vehicle crashes. The good news is the use of child restraints have saved the lives of an estimated 425 children under the age of 5 in the U.S. (2006 NTSHA).