What does the poop look like?
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It looks like your chick has some swelling to the eye? Any mucous from the nostrils?
Seeking vet care is always best so you get a proper diagnosis.
I can only guess, but I feel that you may be dealing with 2 things. Coccidiosis and respiratory illness.
You can find Corid at most feed stores for treatment of Coccidiosis. Injectable Tylan50 can be used treat respiratory symptoms.
The eye does not look good on this little one. Flush it with saline and apply an ophthalmic ointment like Terramycin or Vetericyn.
Do your best to keep them drinking and see if they will eat some wet chick starter.
I'm sorry for your losses.
