That I would have to agree with - the baby should be stationary and the world should revolve around him/her (sorry can't remember)
Thank goodness she has you all to help and guide her. She won't change overnight (no matter how much she needs to) and as you said her mental challenges throw a monkey wrench into the whole business. Just don't give up on her, she'll either meet her responsibilities or she will need your support if the children are removed.
I think I have just seen too much for an occasional drunk up/bake up to phase me.