Xanax, Alcohol, and feeding?

So i just found out that my friend took Xanax and drank alcohol the other night and then was trying to feed her baby. The father took the baby before this was possible, so the baby didn't get any of the tainted milk....thank god!!!! But i am wondering what could have possibly happened to her baby if she did feed him? I have been trying to google it, but all i can find is Xanax and feeding....which is bad if you do it a lot, but almost all the sites said it was ok to not skip a feeding if you only take it once. Anyhow, i know that drinking while on Xanax is totally different. Can someone please direct me to a site that explains the three combined? Thank you so much!!!