Usually a molestor or the people who are sympathetic toward them use the 'relative molested them' story as a last explanation. In most cases, the accused relative is deceased, so no one can truly dispute their claim. I'm sure that in many cases, this has happened. But too often, the molestor says that since it happened to them by a trusted relative, then they were unable to stop and reason that what they were doing was harmful and illegal. I don't buy any of that. They know it's wrong and they know it's harmful. They know they can stop doing it as well.