We had trouble with Sukoshi trying to eat the cats' food as well, and she also seemed to find especially delicious treats in their litter box,
so we put up a little blockade to keep her from going into the room where we keep the cat boxes and food/water. We originally put their boxes and food/water up on a couple little stands that we built, but then we decided it was easier and cleaner looking to just put them back on the floor and keep Sukoshi out. We bought a package of shutters from Home Depot like you'd put on the outside of the house, and laid on their side, they're the perfect height (or width, if you had them standing up like on a house) to keep a little Yorkie out! I hope your baby is ok!