Don't concern yourself with the "sister/brother" thing. These being F1 generation of a cross have so much genetic diversity it's actually in your favor to selectively breed those F1's with the traits you want to narrow those genes into the flock. Or backcross the F1 pullets with traits you're looking for back to the blue egg sire (father).
To add: Being they seem to all carry blue with brown the offspring would range from brown to every shade of green to olive. There is a person on here with thread of making and continuing Olive eggers. Photos of resulting matings and so forth. Try a search.
To add: Being they seem to all carry blue with brown the offspring would range from brown to every shade of green to olive. There is a person on here with thread of making and continuing Olive eggers. Photos of resulting matings and so forth. Try a search.
Last edited: