I think so. David mentions how his little brother used to plant food in the basement/garage and tell their mother that "it" had food again. So mother go down and beat him and do her usual games with him.

But in Richard's first book "A brother's Journey," he explains why he did it and he thought for years David would have a grudge against him and go after him because of it. Sad how fear can make someone enable abuse too. His life was basically bad already and the next target with David home but it got a lot worse after he was taken away.