Children's Roles in Pet Care
A toddler can help parents with pet care simply by being involved - "helping" a parent fill food and water dishes, grooming, going with parents to take the dog for a walk or to the veterinarian. Another good trick is to have the toddler give the dog a treat for good behavior, i.e. gets in bed or crate before family leaves the house. The toddler and the pet both enjoy this special job!
The 5-7 Year Old
This age group is capable of doing some of the tasks above (feeding, watering, grooming) without parental help. Still you can't expect that a child this age will remember to do these jobs without friendly reminders from Mom or Dad.
The 8-12 Year Old
Parents still need to supervise children in this age group for some tasks, like walking the dog. Before a child is 10-12 years of age it's not advised that they walk a dog without adult supervision. But the child can feed, water and play with the dog alone (depending on the dog's temperament and area for exercising).
Depending on your teen's maturity, you can sometimes allow him/her to take full responsibility for the dog, including feeding, cleaning up after, driving to the veterinarian and exercising the pet. Allowing the teen to take the dog to obedience classes can also be a good activity for both.