If your friend lives with your grandparents who are unwell and this creates some problem for him like reaching late at school then for the time period he is in school should keep a caretaker or a nurse for them. That nurse can take care of your grandparents till the time you'll be in school and then after that you can take care of them. Appoint nurse according to your time table. If sometimes, by chance you fail reaching school on time then your school must forgive you after seeing your situation. For that, inform your school authority in advance about your situation. This can help you in some ways.