I tend to think so too, shizam, about her being immature. Or perhaps she's just rude or socially dense. Or maybe she even thinks a thank you via her dad is really okay.
I don't understand why parents and grandparents reward kids or grandkids for doing well in exams. Kids who can will and kids who can't won't, on the whole. How are the ones who do their best but who don't do well in exams rewarded?
What colour car do you have or did you used to drive?

