Parents oftentimes do not know what to do when their young adults cannot learn the information for school. Parents may try to explain it in a manner that their young adults will understand it. They oftentimes will not be able to grasp what is being taught, and the parents may become frustrated. Parents may even make negative comments to their young adults when you have not been hired yet and perhaps even after they hire you when you are there (which really does not do their young adults any good whatsoever!).
As you progress with your tutoring of young adults by listening, answering questions, and explaining in more detail, giving encouragement when the young adults need help and giving praise when deserved have some very positive repercussions. They will feel better about themselves, and they will feel better about what you are sharing with them, because you are breaking down the barrier of "I can't learn this" and "I can't do this". In turn, their confidence level improves, and they more than likely will continue doing very good work.
There is an interesting consequence for their parents. When you share with them and with the young adults in person how their young adults are doing by how they are understanding the information better, the parents may actually change their negative attitudes to being more positive about their young adults, not only in terms of the subject or subjects you are tutoring the young adults, but also about them as individuals.
So, here's a suggestion, if you are not doing so already. Please consider making genuine, positive comments to the young adults and their parents. Such positive comments can change the family dynamics to be much more positive with the ultimate benefactors being the young adults themselves!