Really thank you to everyone who responded!! You each had some great suggestions and insights. I really appreciated the smart conversation several of you had about the possibility that she's paying for her own food with her babysitting money and/or hungrier than she's letting on because her family isn't wealthy. Those were smart things to discuss.
I'm going to set aside a box for her with eggs, bacon, some sausages, bread, a few cookies, and some popcorn. Or some frozen things we don't normally eat. That way, she can have a few good meals, but they are meals worked into my budget, which will be better. And it'll save the rest of us in terms of the food.
Honestly, you all had amazing things to say. I've erased the other post because those kinds of posts feel so personal to me, I fear doxxing. (silly I know)
But, I really appreciate all the input. THANK YOU ALL SO MUCH!!