Ok, so I have a broody hen with about 8 eggs under her. I have marked the eggs she has been sitting on for about 5 days. I collect the unmarked eggs from under her daily. (Yes I have a rooster) I have an opportunity to get some fertilized eggs for a breed I really want. Is it ok to add these fertilized eggs to the current eggs? Or is the time difference going to be a problem. Or could I replace the current eggs with the new ones? Any advice would be appreciated. New at hatching.