Given the growing prevalence of so-called helicopter parents, the meeting of parents and professors has become more common. Although I have never had the pleasure yet of speaking to a parent of one of my students, I have witnessed such an encounter and have heard anecdotes from colleagues. Such meetings are rarely productive and usually do not end well.
Students are adults, albeit most of them are young adults. They should be left to manage their lives including school. Parents should support them with guidance and encouragement. Unless there is a physical or mental health concern, I do not see any need for a parent to contact their adult child’s professor.
If you are a concerned parent, please read this New York Times article before contacting a professor.