If white legs are required in Whites, then most if not all of them would be cuckoo. This is because the main genes that cause black color in chickens also lay down pigments on the legs, making them black. Cuckoo/barring also has the side effect of diluting the black pigment on the legs., an...
The white hen is a cuckoo under her "coat of white". White is not actually an color, it only "stops" whatever colors or patterns the bird has from showing up visibly.
the gene that makes the cuckoo or regular bars is sex linked.. you unintentionally did a sex linked pairing with this hen, as...