AITA to get annoyed each time my sister says I am the favourite?

I, 20 F, and my sister, 29 F, are close and I look up to her a lot. Obviously having a big age gap and very different personalities didn't allow us to be close until I was like 14 years old. So back to the matter, my sister never miss an occasion to say that my parents showed favouritism between the two of us. But I wanna give context. My sister has always been a bit bratty, hot headed, impulsive etc, so sometimes (always) she speaks before thinking and that's why she always got in trouble with my parents during fights. She is an amazing woman, she is hard working, she is an engineer and has a stable work and a boyfriend and lives with him. Mind you, she gets 2000 euros per month as a salary, and the apartment she lives in was once my grandmother's apartment that when she passed in 2021 became my uncle and my dad's possession. So now my sister and her boyfriend lives there, they don't pay rent to my dad and they pay my uncle around 300 euros. it's not to make it about money, even tho my sister and her boyfriend make the same money so they are well off I guess? But they are saving money for a nicer house. My family has the opportunity to give these type of economical help so it's not an issue. Meanwhile I was always extremely shy and submissive when I was a kid, So I didn't get in much trouble as my sister because when I did wrong I knew when to stop instead she kept on going. So she always says that they went soft with me, but I am sure they just didn't have any reason to punish me for nothing. Anyways when I was 14 I got sick with anorexia and depression and it took 5 years for me to heal and these years were horrendous for me and my family so I think that's also maybe a reason why sometimes they seem softer now that I am 20? Not taht they do it on purpose but maybe they are just...scarrred. Anyways I go to university as well, I study physics, I help around the house as much as possible. I am not financially independent but I am very aware with money so it's rare I go buy things for myself, especially if I don't need them. Lately I've taken a job in a bar to get some money for myself. Also I am the carbon copy of my father in a sense of personality, so maybe he sees himself in me. But my sister always says they have a favourite and they don't act equally with both us and I get annoyed when she says these things tbh, I don't think it's very fair. So am I the asshole?