It's good to have a dog growing up.
Robert has an son that is getting bad grades in school who has expressed that he wants a puppy for Christmas.
Robert wants to teach his son some responsibility.
Robert makes a deal with his son that he can have the dog if he improves his grades.
Robert refuses to get his son the dog citing his performance in school.
Robert's son is motivated to improve his grades and is rewarded for good behavior.
Robert's son reacts counter-intuitively and continues to do badly in school.