I am not sure what your question is.
Do all the chicks have black cheek or just this one? Or does this one have different black cheek from the other ones?
I don't really make out the bird's colour very well from this photo, looks like the normal fledgeling colour, though his belly seems rather white. And you often can't tell the colours until they start getting into their adult feathers.
So maybe a better picture? But from what I can see on this one it looks like a typical BC chick.