It is possible that in addition to his mental health status, his 'never holding down a job' and still living with his parents may be attributed to the difficulty one might have in obtaining meaningful work in their desired/trained field when they have a criminal record which includes prison time. Additionally, with his parents being now in their mid 80s, and considering the size of their property, I can imagine they were likely happy to have DG take on some of the property chores, which in return, could have saved them from spending the money to pay someone else to do it. Just guessing, but I'll bet DG was on 'disability' (due to mental health issues?), which would have given him at least some money, and his living there may have made sense for all parties, under the circumstances.
