HELP... 3 day old WC Polish fading

[Carrie211]

I just got 8 new chicks from McMurray and all are well so far except the smallest WC Polish. She's just not thriving. I'm keeping her warm, encouraging her to drink, have given her SQ fluids, fed her some yolk and still she doesn't want to thrive... anything I'm missing, or something more I can do???

These are my first chicks and it's hard to watch the littlest one just fade away