i have a flock of barred rocks and amauracana hens, about 6 months old. all are laying but one is having issues. every other day she lays one bigger egg with 2 yolks...the shell is fine. the next day she lays 2 eggs, not in the nesting box, and each has only one yolk but the shells are like latex. all the other girls are laying perfectly normal eggs. any ideas ?