I call it the Kazoo crow. I have 1 doing it every morning competing with the big boysWaiting for pullets to lay is like waiting for jello to get firm. They will lay when they are ready and not before. Roos dont really affect laying at this age. You probably have more time to wait than what you think. Your boys will sound funny and awful until they get their big boy voices. Mine sound like someone is squeezing them. However, be careful what you wish for cause they can be loud and proud! lol.
