Seams like we are slowly seeing each other clearly. I agree that some seam to be trying so hard to place all the blame on one party that they refuse to acknowledge the fault of the other party. Also there are those that try make it out that the woman's actions are worse than the males.

The male is the (if I may use the word) most guilty because his crime is abuse of a child by and adult. Now matter if the woman swore at him, this is no reason to touch the child. If I swear you you, then hit me not MY child. 

The child that hit the other one in the face is also guilty this is assault, your welcome to ask my kids if I treat them different,  there is no excuse (save for protecting you life) to punch someone in the face.

The mother carries some guilt she should not have provoked the man by swearing at him, prior to him grabbing her child. Also when he walked away the first time she should have left it there instead of provoking him further. ie 2 ill-disciplined adults.