As the article explains, we feel empathy for people who are most like us. Children and other victims may not look like us as much as the abuser does. We might even know the abuser and not know the victim. The mentally lazy thing is to let our familiarity with the accused abuser blind us to the reality of what is happening. The way to get out of that is to focus on the humanity of the victim just as much. When you have empathy for everyone, regardless of whether they are like you or not, you can react to the situation in front of you instead of your bias about the people involved.
Everyone deserves that. No matter how different they may be from us.