GH Sam, what exactly happened?

to her that she is all riled up about Kristina and the beating? i know its her sister and no one should be hurt like that ever, but the way Sam is acting and bringing up her past if i remember correctly, she did get hurt by a guy cause of her actions and the cons she was pulling back then..but other than that i don't remember anything else...i mean like a bad beating just because you know..so can some one refresh my memory..thanks GH fans!