If her memory should fail, or if she should make a false step, he would not hesitate to push her.
You have pleaded your youth as an excuse for your first 'false step,' as you call it.
One false step and you are over a precipice, or up to your neck in a slough.
Dubois felt that he had taken a false step, and remained silent.
He had taken one false step, and he had been held ...