So the past year my sister was accepted into Yale, UPenn, Stanford, and Duke; she even got a likely letter to Yale. She eventually decided on Penn, so I’m wondering if the fact that she turned down Yale, Stanford, and Duke (among others) would reflect negatively on my applications this upcoming year to the schools that she turned down (she’s class of 2021; I’m 2022).
No. Her decisions will not affect your applications. Congrats to your sister and best of luck on the upcoming college applications.