What ever is worrying you so much?
;-)
Have you been brainwashed by the milk marketing board?!?
Dairy, especially cows milk, is NOT necessary nor particularly healthy and so you have NO need to try to get her to drink it!
Since there are many better and healthier nut and soy milk alternatives etc for those that want a milk type drink or need it for any recipe - there is NO need to have cows milk at all.
Think of a cows unique stomachs, think of their kind of vegetarian diet, think of the kind of body cows milk is produced to build. Still see any need for it?
Bear in mind that ALL other mammals are WEANed off milk it's just for the very immature animal. The toddlers and adults do not / cannot drink it. We should not be drinking it in adulthood either BTW certainly not that meant for a totally different animal! It's been shown for years and years that it just clumps up the intestines and may hardly be digested. But it's socially accepted now (like cigarettes used to be).
There's simply too much invested in its production for everyone to be made aware of what I'm telling you...
So relax!
We often crave foods we need or dislike those not good for us - it's possible that your family instinctively chose best!