We can't sleuth his family, but I don't think they were *that* wealthy (at least not by the standards of the richest people in MD nor NY nor CA or any other high CoL place.
It is my impression that his family has gone public about their own medical issues and inability to pay for two members' bills. His family owns a funeral home; his closest relatives have jobs - well paid jobs, but still jobs that require a lot of hard work (medical doctor, for example).
The family of the suspected killer of CEO Brian Thompson shared a statement about their son hours after police arrested him.
www.usatoday.com
I'll report my own post to make sure this link is okay.