I have had students who did not pay me directly, and I have tutored one student who did. I cared very much about her, both as a person and as a student. I still do, even though it's been years since I last saw her. The method of exchange of money made no difference to me -- actually, since I tutored her personally instead of in the midst of a class of several students, I had more of a bond with her.

But no, I didn't care about her like I care about my little brother, who is the same age. Particularly while I was tutoring her, boundaries needed to be in place. Still, I wanted more for her than just a good grade at the end of it, which is all I was actually getting paid for.