My nephew is 15, is autistic and has ADHD and lives in a small village. In the summer, he got new neighbours move in and more recently it's become very scary.
A bit of context, his bedroom looks over the front of the house, where he can see the gate to the front door, the road and pathway and the lounge window is the front of the house. His grandparents live up a few doors up and his parents park on the main road.
Recently his neighbour has started complaining about my nephew looking out his bedroom window or lounge window when they open their own gate. This included the neighbour yelling at my nephew and sister-in-law calling my nephew horrendous names. The other night he went out to look at the stars with an app on his phone in his garden, and this resolved in a tirade of abuse and C-word being yelled at in. My sister-in-law was going to talk this through with the local police, however before she got a chance this escalated. The neighbour threatened my nephew and my sister-in-law had to get the police out. The police came and tried to resolve the situation, but with limited success. The neighbours are already known to them, I don't know why, and the police had told my nephew to dial 999 if it happens again.
So my question is, is there anything my sister-in-law and nephew can do, to feel safer in their own home?