Are you saying babies are not born tabula rasa? I do not believe they are.
Well, the bible does say to know to do good and not do it, to them it is sin.
David wrote "Surely I was sinful at birth, sinful from the time my mother conceived me."[Psalm 51:5] Then he wrote "Even from birth the wicked go astray; from the womb they are wayward, spreading lies.Their venom is like the venom of a snake, like that of a cobra that has stopped its ears,that will not heed the tune of the charmer, however skillful the enchanter may be."[Psalm 58:3-5] So, we are born sinners and when we grew enough to put it into action, we sinned. An infant will take things they know are not theirs, and that is stealing. They will tell you a big honking falsity to keep from getting their 'bum bum' heated, and that is lying. When they get mad, they will slap, scratch, scream, bite, because they did not get their way. Babies are not the 'sweet little angels' ppl make them out to be. My wife and I do not have kids, but I've been around enough nieces and nephews to know, see and feel their hatred when things do not go their way.
Well, they do know from their parents what is right and what is wrong. They know that if they get caught, to try to lie or deflect the blame to someone else to keep from getting into trouble.