Just over a month ago I added 3 new POL brown chickens to my flock. They are from a large local breeder and all the same age. Now I have a total of 6. One of the new chickens started laying small eggs immediately and hasn't stopped, but the other 2 still haven't laid an egg. It's on the warm side of spring now in Melbourne so I don't think it could be too cold for them. Any ides on how to get them laying?