Two week old mille fleur d'uccle chick standing by herself looking a bit Lethargic

[swadle]

I have a small mille fleur d'uccle who stands by herself with her head not extended with her eyes close and wings down quite a but. I see her eating and drinking. When I give them small treats she will "wake up" and run over and join the over chicks. Do chicks get a little "lethargic" when they are growing?