I've shared it here, and often, before. My ex-husband was charged with raping his then 14 year old niece a few years ago. There were absolutely NO warning signs to ever think him capable of such a crime. He was 44 years old at the time he committed the crime against her.
This was a girl whose diapers he'd changed - who was more like a daughter to him than ever a distant relative - and he drugged her, then raped her, then threatened her should she come forward. She bravely did so, eventually, and he plead guilty to avoid a trial and the potential for a far longer sentence.
Everyone who knew my ex (including myself) was dumbfounded. The vast majority of those he knew adored him - thinking he was a nice guy, charming, likeable, helpful, friendly, gregarious, etc. Some of his family members still protest his innocence.
Incidentally I'd filed for divorce just 6 weeks before he raped her. I've often wondered if that wasn't a trigger somehow - though obviously the blame lies squarely with him.
Predators always start somewhere. Some will have a history, some will begin committing crimes younger - but it's the belief that every one must have a history, a look, a pattern, that allows other predators, who don't, to thrive.
MOO and FWIW