I was about 8 so a bit old for you OP, but I thought I would post anyway.
I don't remember any rows, although I remember feeling bemused and interested at finding several broken mugs on the floor beside the wall one morning, where my Mum had obviously thrown them at my Dad.
I do think part of a child's reaction depends on how/why parents split up. In my parents' case, my Mum felt totally emotionally neglected by my Dad and she had been miserable for years. Dad, on the other hand, was quite happy and thus had no interest in doing anything to help her be any happier. When she finally couldn't stand it any more and pushed for a split (this is a huge simplification by the way) he took it very badly.
My Mum was careful never to say a word to us against my Dad, no matter what he said about her. She explained time and time again that he was not a bad person, but that she just didn't love him any more and that she was sorry to do this to us but she couldn't go on being married to him. He was - understandably - very bitter but Mum used to almost make us see him, well she used to make my 14 year old sister phone him to arrange for us to see him, which she was often reluctant to do in the early days as Dad was not always pleasant company at that time - he would never had been violent but it could be a bit uncomfortable. This might seem mean but it kept our relationship with him going and my eldest sister was, to his dying day, his favourite.
Dad kept her very short of money but she never complained, she always made it clear that breaking up was her choice. As we grew up we all could clearly see that Dad was emotionally distant and all came to see why she couldn't stand to be married to him any more, but largely because of her efforts in the early days we all had a good relationship with him. She still feels bad about breaking up the family but I actually think it is better that she did, I think I had a better relationship with Dad than if I had had to live with him when a teenager. My stepfather (whom Mum also later divorced) was a totally different kettle of fish, fun, affectionate, generous and in a lot of ways a far more openly loving Dad, and I have lots of happy family memories from my teenage years involving him.