My toddler is too young for cough medicine, so this "remedy" was prescribed by the on-call nurse I spoke with. You can give it to kids as often as their cough is consistently irritating, and as she said, "you can't overdose on it."
Bring one cup of apple juice and two tablespoons of brown sugar to a boil. Boil over medium heat for 10 minutes until it takes on a syrupy consistency. Allow to cool and dispense in 1-2 tablespoon doses as often as needed.