It shocked them that they’re son had ended up in jail. The mother went hysterical and the father had to call in a doctor.
The family get treated like if they had helped Gav with the kills.
They are being treated like if they had been a part of the murder, that they were bad people.
They are scared that maybe they will put themselves in danger when they are close to them.
They want to let the people know where they live so they can keep an eye open. the newspaper thinks it’s their right to know where the family of the killer is.
I think it's wrong that the whole family has to suffer because of one person. But I couldn't come up with a better solution.