Sometime, it all just clicks after you meet the parents!
"I teach college classes so I don't normally meet my students' parents, but here's a backwards example of meeting the mom and having it click later.
I used to teach at a community college where it wasn't that unusual to have family members in the same class. I've had a lot of siblings take classes together, once a husband-wife pair, so it didn't strike me as that weird when a woman introduced herself and her son on the first day of class.
Except the mother was not on the attendance sheet. She was not registered for the course. I double-checked with the administration and learned that she wasn't a student at all.
I talked to her at the end of that first class and told her that, unfortunately, this class is for students only and she was welcome only if she registered for it. She said she had to be there for her son, that he needed accommodations and she was there to provide them. I told her in that case her son needed to get official documentation from the disability services office and then we could work from there, but short of that I couldn't allow her in the classroom for the sake of the other students. She said that was fine but, unsurprisingly, nothing ever came of it and I didn't see her again except to drop off or pick up her son.
His attendance was perfect but his in-class work (what he managed to turn in, sometimes he'd sit there doing nothing) was drastically different from his take-home assignments... Mom wanted to be there to do his work for him. He had gotten so used to his mother doing everything for him and saw no reason to change that when he got to college."