Aha! Being a former Virginia school delinquent I can help! Plus, you said Google-Fu, I’m yours, dahling. If he’s registered in school it’s my understanding that the parents are held accountable for unnecessary and frequent absences. Once he misses a few days, the school will figure it out. She might need to contact the police, but if she’s unwilling to do that you should know they will become involved eventually as a means of protecting the child. I was frequently absent and I was charged with truancy, my mother was also held accountable. I was in high school at the time, but that’s all the info I have. Hopefully, I’m getting it all right. Good luck to you, your sister and her child.