Oh! I know one! It's called "The monster duchess and contract princess" Though there's not much romance in the recent chapters yet. It's not much of comparing but more on being biased to the other sibling. It's a good story! Hope this helps :))
im sorry but i cant take "hetero romance" akssjsjajsj im dying
http://www.mangago.me/read-manga/seiyuu_ka/
This one, the mc is really strong even when her mother obviously loves the younger one
HAGAGHAH idk what to call it
thank you!!!
any bl or like shoujo romance (hetero romance?? what do you even call it) where the mc has a sibling that they're always being compared to bc the other sibling is "better"?