<prompt> Human: My little sister is 17 years old and in need of a car. Her and my parents do not have enough money at one time to outright buy her a car. Obviously, she is too young to get a loan on her own as she is not 18 and does not even have credit. My parents have too poor of credit to cosign or help her in any real way. Im in my 20s and have what most would consider a very good credit score. I hinted to my father that maybe cosigning for her was something I would do, however, I never said outright that I would. My sister has shown me in the almost 3 years that she has worked that she is responsible and entirely capable of paying something such as a monthly payment. However, I know that all of the risk is on my shoulders in this situation, and not hers. I am hoping that somebody can explain to me why cosigning may be a bad idea if the person is someone I trust and that is very responsible. Also, I have heard but do not know if its true that if you cosign for a loan before someone is 18, that you can be removed from the loan after the person turns 18. Is this true? She turns 18 in a handful of months, FWIW.  <response>: If she cant pay, youre likely to either have to step in to deal with it yourself, or kiss that nice credit score goodbye.A much better life lesson would be to teach her to save for a car outright, since thats hands down the best way to use money safely and efficiently, but thats not the scope of your question 