Aunt refuses to drive her 14-year-old nephew to his sports practice after he repeatedly screams at her: 'My sister-in-law said he has been like that at home too.'

She didn't sign up to be an unpaid chauffeur to a spoiled, rotten brat

If you choose to participate in carpooling, there is a large chance that you're going to be responsible for transporting the most annoying kid in the world. My family did our fair share of carpooling to extracurricular activities when we were kids, and my parents still remember the names of the most irritating kids who ever rode in their car. Suffice it to say, we did not continue the carpooling relationship with those families. There's only so much you can take, and screaming in the car for 20 minutes is understandably intolerable. 

Nobody loves driving kids to and from soccer practice, but it's a job that needs to be done if you live in a suburb where kids can't get themselves around. There are ways to make chauffeuring your teenager around town more tolerable, but even if you have a great kid whom you love spending time with, it can be quite a pain. If you decide to become a parent, you agree to do everything that entails, including driving your child to their extracurricular activities, no matter how miserable it may be. If there were a world where kids could safely take Uber to their baseball tournaments, that would be great if your family could afford it. But that world will probably never exist, so unless you live somewhere where a 13-year-old can take the bus or the train, you have to live with the car line at least until they turn 16.