Is she Exclusively BF? That's what I assume by your title. If that's the case, I wouldn't worry about giving her cows milk, I would just give her other food. You can certainly give her cows milk if you want too, but there are other foods that have calcium and protein in it too. If she is 2 years old IMO she should be eating solids of some sort. I don't worry too much about making my 2.5 year old drink cows milk because she is still nursing, but I do offer it to her. Some times she drinks it, some times she doesn't. Just offer your DD healthy food choices and she will most likely get enough to eat. 2 year olds are notoriously picky eaters. If she is growing well, healthy, happy and acting normal, I wouldn't worry about it.