Altering the Quraan

Q: I know that the Quran has never been changed. Did it happen in the history that someone tried to change/add words to the Quran? I know for sure if someone did it, they would fail miserably and it would be discovered because Allah protects the Quran. Just asking if someone actually attempted to change it.

Leftover milk of a dog and cat

Q: Please may the general ruling on 'circumstantial evidence' relating to the Soor (leftover) of animals be explained. I heard an example of a bowl of milk and a dog, but I cannot remember the particulars. We have cats at home and I am unsure when to consider something pure or as makrooh soor (leftover). If appropriate, please may the milk/dog example also be given.

Father getting his non-baaligh daughter married

Q: From what I have read on the internet, a father can force his daughter, if she is prepubescent, to marry someone against her consent so long as it serves a clear interest for her. This deeply disturbs me. Just because it serves an interest for her, this absolutely does not mean that she will want to be married of if she is ready for it. If she is forced to be married to someone she never wanted to be married to, then she will forever live her life being extremely depressed, resentful, and ungrateful regardless of serving an interest. This is common sense. Is there any way she can get out of a marriage she never wanted to be in?