I agree that if you must go visit your child, then you should first contact the host family to see if it is okay. But what is the purpose of sending your child to study overseas if you are going to be there? The purpose is for your child to learn English, immerse him or herself to the American culture, and be independent. Your child can't do that if you are there all the time. I know it is hard to let go of your child but he or she must learn on their own.