Polish Chicks

[tigermissy77]

I have 7 polish chicks now 8 weeks old
3 have crests and 4 dont is this normal?

 

[muddy75]

are they hatchery stock? I found with silkies that hatchery stock birds can show a lot more variation than breeders. But i’m no expert with polish as I’ve never had them. But that would be my guess. @sourland anything to add??