the thing is if a majority of us look back to when we were 13, we wouldnt even have thought about having a baby. for a majority of 13 year olds that are having sex, then a baby is not what they are after. but i do think that she needs monitoring. to start shouting at the baby for no reason is not right.
i dont think it can be blamed on her because she is 13 / 14. I am how many babies do you hear about being neglected or murdered by parents over the teen years.
Like what sami said, i amsure that she will be okay, she just needs a lot of help.