Has anyone else experienced their hens sleeping in? My chickens used to be up at the break of dawn screaming loudly for their breakfast. Lately they sleep in, refusing to get up when I open the coop and sometimes not even coming down for breakfast. The other day they slept until midday. Right now it's 11am and they are only just waking up. The mama hen is about 3.5 years old and her daughters are 2.5 years old. They are silkies. Is this normal?