A 1970’s made for tv thriller Bad Ronald.
I don't think I ever saw that one. Just checked it out on IMDB and it looks very interesting. I see it's available for purchase on DVD, but it's not available on Netflix. It's a shame that a lot of the made-for-tv horror/thriller movies have never been released on DVD as I remember several that I would like to have copies of. Among them: "The Ghost of Flight 401," "Crowhaven Farm," "The House That Would Not Die," and others.
I remember that one. Crazy mom locks up nerdy son who killed a girl who teased him. Then she dies. New family moves in. With a teenaged daughter.