OP - I would be concerned that your chances will be less at a place like Yale because you have a stronger resume than your sister. Very possible that yield protection would come into play and the adcoms could think that you would say ‘no’ because they denied your sister, so they may as well not take the risk in offering you a spot. Honestly, I don’t think your sister’s GPA makes her competitive at Yale (or the like).
My opinion is if you do want to go to school together, make a school list based more on her stats, not yours. You’ll have more admissions success.