I'm waiting for my Silkie Machine to go broody. While I wait.... 1. How long do fertile eggs stay viable? I want to hatch certain eggs, and I started putting some aside, but want to know how long they stay good. 2. Is there any way to find out which hen is laying the egg other than seperating her? I know who lays which, but some look exactly like others when together. I seperated the hens to find out, but I don't want to have to do this constantly. I think I heard of something like food coloring/ dying the vent??? Thanks!