C.M.
She could just be on a "grow" and truely be hungry in the night. (So happy you are not a "cry it out" mom. I wasn't either. ) Since she does have other tummy issues besides maybe being hungry, I have no advice, except that when she does get up...feed her if she is huingry, no talking, no lights, do not let it turn into playtime. I believe you are doing the right thing getting up with her. I was a "bring them in my bed so I can sleep" mom. This will pass.