Welcome To BYC
The OP (person you are quoting) has not been on since 2021 and the thread is from 2020.
Can you start a thread of your own or at least post some photos along with adding some information in relation to your chick and her symptoms?
Photos of Chick, her poop, the brooder setup, temp of brooder, what you feed, etc.?
Is she spitting up water on her own or when you pick her up?
When are you feeling her crop - when she's been eating/drinking? Is it emptying at all?
Is the chick pooping?
A crop that is not emptying and like a balloon may have a blockage - do you provide chick grit for your chicks?
I'd work on hydration, get some coconut oil into her and see if that gets things moving.