<prompt> Human: Hello, Im finishing up my last year in undergrad and I am lucky enough to have a job lined up after I graduate. Total compensation around 90k.After taxes and misc. expenses I will maybe have around 40k to spend. Of course I would like to put it all in savings but my younger sister is starting college private so 50kyr. She will probably not be receiving much financial aid because my family makes too much money. However, atm we cant really afford to pay all of the tuition because somewhat recently my parents went through a contentious divorce that devastated our finances. What the financial aid office sees is that my father makes 350kyr and my mother makes 200kyr. But what they dont see is that my father basically took half of my mothers savings and hasnt given me a cent for my education so far he is unwilling to pay and out of the picture. My mom has nearly burned through all of her savings 20k in her bank account paying for my education after the divorce, and since my mom is nearing retirement age I really want her to be able to rebuild her savings by helping to pay for my sisters education otherwise she will likely need to take out student loans. I have no problem throwing 100 of my discretionary income at her tuition but Im not sure if that is wise.Basically, I was wondering if the benefit for my sister not needing to take out loans exceeds the benefit for me to saveinvest my money. Any insight would be appreciated.Im very unfamiliar with personal finance in general so please excuse my ignorance if this sounds really stupid.Thanks.Edit: Just to be clear the private school she will be attending is a top Ivy, so we think it will be worth the 50k.  <response>: It will almost always benefit you better to be selfish and take care of yourself. However, family is family. It sounds like you arent terribly worried of not having the money for yourself or ever getting it back. Your sister will most likely end up with loans at a minimum of 6.5 you could potentially loan her the money for 1-2 to keep up with inflation. 