A new study found that kids could be safer riding in cars when grandma or grandpa is driving rather than mom or dad. Older drivers may have a bad reputation but the study looked at the number of injuries rather than the number of crashes, and found that children's risk of injury was 50 percent lower when riding with grandparents than with parents. Researchers had a theory to explain the findings, writing, "Perhaps grandparents are made more nervous about the task of driving with the 'precious cargo' of their grandchildren and establish more cautious driving habits.