This is a tough one. I have to disagree with naive on a few things I'm afraid.
Children assume that parents are honest with them, and even we as adults have a very hard time dealing with the lies, the manipulations, the crazyness. Alcoholics don't stop lying when it comes to their children, they lie to them and manipulate them also.
I don't think this is in any way healthy for the child, and quite frankly I'm uninterested in what is best for the alcoholic.