Whose to blame Whose to blame for what happens in "A Good Man is Hard to Find"

The
grandmother is at fault for what happens because it is she who insists upon visiting the house
that she is "sure" to be down the road they take.  If it were not for the grandmother,
the family would not have (a) driven down the road or (b) the cat would not have jumped upon
Bailey, causing him to lose control of the wheel and have a wreck, or (c) the Misfit may not
have felt it necessary to kill the family without grandmother's verbal expression of recognition
of him as the Misfit.