(Before I begin, I want to say that I’m sorry if my interpretation of this is off at all. I just woke up. I’ve put why I think what I think in parentheses)
This was very good! It took me a moment to find the poem’s rhythm, but once I did, the poem was very fun to read.
I like that you did it from the perspective of someone who’s parents clearly tried their best, but still let enough favoritism through in subtler ways (“Yet we had the same things/Our parents had a glance/That made me realize/They loved you more”) that it still affected the narrator. Their daughter was raised in the shadows and they didn’t understand when they saw the effects of those shadows on her, making it worse (“My judging glare/All because/They refrained/To care.”)
I’d write more or go back through to double check what I’ve written, but I’m in a hurry write now. Overall, I really liked the poem. (I could come back later to offer some constructive criticism, if you want? I don’t know if I’d find anything, but I could try when I have time)