I got a flock of 7 chickens in the winter. I also have 1 rooster and 3 chickens from an original flock. When the new ones arrived, nobody was laying for about 3 months. Finally, they started and eggs became plentiful. One of the original birds went broody, so I decided to let her hatch them. The eggs never hatched, and I eventually had to take them away. Since then, none of my chickens are laying ANY eggs. Why is this?