Kate, I would like to add my voice to those who are advocating for your mom’s college.
When you say that it’s small, I’m wondering how small? Is size the reason why neuroscience is only offered as a minor? Meaning that they don’t have enough faculty to offer the full range of courses? I’m wondering if there is a way to work around that. For example, many colleges allow for a semester or even a year at another college. Study abroad is the most common form of such a program, but many colleges allow for the same thing at colleges in this country. By studying at another college either abroad or domestically, you could probably get the courses you need to turn the minor into a major - and you may be able to do it at a college with top professors in the field.
Does your mom’s college provide the option for individualized or student designed majors as many colleges do these days? If so, you can use the semester or year at another college to have your coursework recognized as a full fledged major.
Obviously the tuition exchange program is also a fantastic option.
Best of luck.