I am going to a wedding for 2 nights in about 3 weeks and will be leaving my daughter with my mom. She will be 7 weeks when I have to leave her. I have been exclusively bf'ing and have been pumping everyday trying to build up a stash for my mom to feed her with. I barely make enough for a single feeding each day. I am afraid that I am not going to pump enough for the entire weekend. If worse comes to worse and she needs to be fed some formula, what is the best kind? and could she get sick from all of a sudden having it? any suggestions for what i should do?