He absolutely did not HAVE to have 'been abused' nor to have 'learned it from some dirty old relative man' like Carl.
By the time I was 8, I knew the birds and bees, and I'd seen a Playboy.
By the time I was 9, I'd looked at all the pics in the Joy Of Sex, and played 'spin the bottle' with girls old enough to be in ... the beginnings of puberty.
By the time I was 10, I'd read the juicy parts from the Happy Hooker, including the lesbian stuff.
By the time I was 11, I'd seen both Penthouse and Hustler.
I was in no way abused by any adults, esp. not my parents or relatives, and none of the ones in my life ever 'taught me' anything, other than the 'basics' you're supposed to be taught. Everything 'else', I discovered on my own, out of curiosity.
Let's just say, in the 1970's (at least in California), people didn't do a great job of making sure there were no Penthouse's in the bathroom when little boys came to visit, or copies of Joy Of Sex on their bookshelf.
So yeah, at 11, I was intensely interested in girls, and seeing their 'secret parts', or getting them to 'touch me down there'. At 11 y.o., I'd probably have seen a 9 y.o. girl as 'old enough to play with', though I don't recall it ever 'happening'.
Yet, I grew up, and I promise I've never abused any kids. Nor was I ever 'abused' ... though I was fondled by a kindly/grandfatherly-looking old Chinese man on a crowded streetcar in Hong Kong briefly when I was 13, gave me a bit of reach around while rubbing his bone against my back, shit-eating grin on his face. He looked like someone who'd be fixing your watch for you in the shop he's had in Wanchai for 40 years, like 'classic' Nice Old Chinese Man.
Anyways, I squirmed away after a minute or two, and got off at the next stop. I suppose that if you run around at 13 y.o. as a pretty white boy, on crowded public transit, in a foreign city of 7M+ people ... eventually SOMEONE's gonna creep on you.
Edit: So ... why I am telling you all this, you may be asking? It's because you're wondering about something of a 'worst-case scenario' ... with regards to your own family members.
And obviously I have no way of knowing one way or another, but I AM here to tell you this ... you may entirely right in what you're imagining ... but you also may be wrong.
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