The only thing is, well, how do you know?  If he had truly raped her, do you think she would be so comfortable around him, and why isn't there any signs or indications that something so serious happened?  Is it possible she just said it, why she would lie I don't know, but is it possible?  I don't know what she'd gain from lying but then again, does it seem like something he could be capable of doing?

I know it would be really sick for someone to lie about something like that, but then again, some people think it's funny, like a way to test how loyal you are or something, I don't know.  Some people's minds work in a strange way.

From what you have said, it doesn't sound right, and I think you should have a little caution about believing her.  But how and if you will ever get the truth, I just don't know.  If you mention something to him, it could start a whole series of problems, and usually, it will come back to you as if it's your fault for mentioning it.

It's a hard one to deal with.  Personally, I would maybe not take it as 100% true for now, and use your sense as things go on.  It's probably the only thing you can do without breaking up the whole family with the allegation, true or not.

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The only good thing about breaking up
Is the making up we do after