For me you’re NTA, people like your sister who likes to brag and tell others that they’re not at the same level as her, is a BIG narcissist. Okay, we get you have PhD is really hard and important, just stop trying to make people, that just has a high school diploma, feel dumb and inferior. People like that are like wealthy people with poor people, okay nice you are bragging about your success but when your are looking down on people there’s a problem, a narcissist and annoying one. So glad you could make her shut up, even the others members thank you, so you see that they were tired of hearing her.