Baby chick not growing feathers

[FathertoFeathers]

I have some jersey giant chicks that are four weeks old and all are growing out feathers and doing fine except for one. She is a bit smaller then the rest and only has adult feathers on the very end of her wings. Other than that she only has the little baby fluff unlike all the other chicks. Why is this? ( they are currently inside but they don’t have a heat lamp on and haven’t for about a week and they go go outside regularly for playtime)

 

[floppysquirrel04]

Is she getting picked on?

 

[FathertoFeathers]

Is she getting picked on?

That was my thought initially but as I watched them more closely she gets along with everyone. All of the baby chicks get along very well.

 

[FathertoFeathers]

Is it possible that she could have the frizzle gene?