Make sure to push your sister through school

They're usually very close to you and you know them better than anyone. They don't want you to fail, but if you do, they'll still take care of you and help you out, and vice versa. If you get too close to failing, your sister will likely take you down with you due to others thinking you might be "getting help" in the wrong way. But you two will still be there for each other. Trust me, no one wants to see you succeed more than your sister.