Found the second egg today. It was broken. We found the first egg up on the roost, balanced on the flat side of the board, 2 days ago. No egg yesterday. This morning, we opened the pen to find that another egg had been laid while up on the roost and it feel and broke. I have 2 milk crates on the floor of the pen, each with a golf ball in it. The girls are not using the nest boxes. How can I break the new and only layer from laying while up on the roost before the others follow her lead? Please help.