Dark Cornish not growing wing feathers

[Saddley]

we have a dark Cornish that has not grown most of its wing feathers. All the others have. What’s going on? Pics are of the chick in question and it’s batch mate.

 

[Henriettamom919]

Could it be it's not getting equal access to food? Interestingly there is another chick whose also a late bloomer- Dark Cornish, meet Monkey Lizard chick!

https://www.backyardchickens.com/threads/chicks-feathers-never-came-in.1316253/page-2#post-21458013