Doug, the 17-Year-Old Brother of a Friend of Yours, Bought

Doug, the 17-year-old brother of a friend of yours, bought your old car from you three months ago to get him to and from his new job. He needed a car because there was no public transportation in that area. You agreed to let him pay in 36 monthly installments of $200, but he has paid you only once so far. Yesterday, you asked him to pay up and he told you he had spent all he had earned. When you told him you would have to take him to court, he said that an adult cannot sue a minor on a contract. Today, a tow truck left the remains of the car in your driveway; it had been so badly damaged in an accident that was Doug's fault that it was a write-off. A note on the windshield said "Your car doesn't run too well, but I won't sue. Let's call it quits. Best wishes, Doug." Under your contract he was to have insured the car, but he did not.
a. Discuss whether you have any recourse against Doug.
b. If Doug had bought the car, simply for normal driving, would your answer be any different, and why or why not?