Kentucky officials have begun fully enforcing the state's booster seat law for child passengers.Erin Goin with the Kentucky Office of Highway Safety says the law was actually passed last year, but there's been a grace period for parents to purchase booster seats.The law requires that children under the age of seven and between 40 and 50 inches tall be secured in a booster seat. Goins says violators will no longer just be given courtesy warnings."They will be issued a $30 fine. They do have the option of purchasing a booster seat instead of paying the fine," Goins said.Gois adds that her office recommends keeping youngsters in booster seats until they are at least 57 inches tall.