Her 13 year old son does all the housework and chores, she does NOTHING - isn't that taking advantage of him?
Wow, if I had a dollar everytime I've heard my sisters teenagers complain of how many chores they have to do, I'd be filthy rich. Fact of the matter is they don't really have many chores at all and none on a regular everyday basis.
This is slightly off topic but kinda funny. We went camping with my sister and her family for about a week. Each time the garbage needed to be taken out we would call for one of the older kids and ask them to take it. My four year old kept protesting that he wanted to take the garbage out, but we didn't let him as the bags were generally too full for him to handle. The last day of our trip we had a garbage bag that was only about half full and figured the 4 yr could manage this bag. We called him to take the garbage and he was thrilled to finally get his turn. He took the bag happily and started toward the big garbage cans. After he took about a dozen steps he dropped his head, put out his lip and said "Why do I always have to take the garbage out." Guess where he learned that. It was hilarious to say the least!