Need a film title please! :)

I've been looking for a film that I saw many years ago. Unfortunately, Google and I aren't getting anywhere. It could of course be that I'm getting something mixed up :D even ChatGPT is desperate about it.

A woman and her child end up with a crazy family. I think she wanted to visit her sister but then got lost, or the car broke down. They are being held there because the crazy mother of the family thinks this woman is her sister. The crazy mother's husband (I think he looked like Tom Sellek) takes the "normal" woman's car apart so that they can't escape. I think it was a red Chevrolet. In the meantime, the normal woman's daughter (I think she's about 10 years old) is with the crazy woman's teenage daughter. At some point, the teenager ties the little girl by the neck to the end of the bed with a leash. The little girl wants to escape and claims that she is afraid in the forest so that the crazy woman's teenage daughter will go out with her. The crazy teenage girl then goes to a well in the garden and takes out her dead baby brother in a box to show the little child. The father had suffocated it because it had screamed so much. The child uses the distraction to run into the forest. There it is found by a policeman. At some point the husband misses his lost wife and daughter, whereupon he looks for them. He finds them and a fight ensues. The house starts to burn and the crazy other man hallucinates his father in a wheelchair, but his wife is sitting there and he shoots her... It was more than 20 years ago when I saw the film (it was on free TV at night, by the way), so the summary is a bit confusing, but I really hope you can help me anyway.