Sister trying to convince herself she's as thin as me (Don't let the title confuse you, I do not really see myself as 'thin')  Okay so I'm not sure if this belongs here because the sister in question is a healthy bmi(I think) but she's visually at least skinny-fat. Her and her twin have both put on a lot of weight since graduating high school, her sister more than her. When we were younger she would always laugh and make fun of me because she was thinner and had a bigger butt(this was when I had a bmi of about 23, idk what hers was but she was more toned). Now the tables have turned. Despite this, whenever she sees me eating she says I'm "eating like a fat person" and makes fun of me for apparently having a flat butt(I'm perfectly okay with having a 'flat butt' if it means I get to skip out on the gut). Today we went shopping. She said she didn't feel like trying on clothes and told me to do it for her, despite me and her twin saying that made no damn sense since I'm smaller than her. She also made me try on size 7 jeans, even though I'd already tried on 5s that were too big. Her argument was she could fit them when she was my age. Makes perfect sense. They were falling off of me and she was trying to convince me that fit, and when I tried on size 3 shorts that were a perfect fit she told her sister that they were too tight when we didn't get them, even though my only complaint was that they were too short.  The amount of denial is amazing. She just can't stand the fact that she's not the thinnest in our immediate family anymore, and that not only am I thinner than her now, I'm thinner than she was at her thinnest, too. Tldr: small-fat/skinny-fat sister in denial about me being smaller than she was when she was my age and thinner than she is now, while also trying to hurt my feelings about my size and eating habits