Or, as likely, boy dies because man pushed him down stairs. Girlfriend knows. Man kills girlfriend to silence her, but tries to make it look like a suicide.
Sure because a man is always the killer.
If so, Lt Columbo would note that he forgot something. Namely, the electrical cord binding hands and feet of the putative suicidee.
It sounds more like “me and the kid have had enough we are leaving”, the answer, “the only way you leave here bitch is in a body bag”, end of case. Now she had to be guilty, just like the old black gal in new York.
“Or, as likely, boy dies because man pushed him down stairs. Girlfriend knows. Man kills girlfriend to silence her, but tries to make it look like a suicide.”
Or, boy falls down stairs, girl feels responsible, hangs self. Suicide is the most sincere form of self-criticism.
Or the place is haunted. I could go either way.