I have 9 girls and one boy---3 girls and the boy are from last year, and the rest 6 girls (Americana) were hatched in Feb this year. The three older ones are good layers. the younger ones are not as good. for a couple of weeks now, I can get 1 to 0 eggs per day. I saw some broken shells in the coop today. I think they are eating their own eggs. what should I do? Help!!