I have an EE hen who has decided to set on the 4th egg she has laid. Her 1st egg laid a wk. ago. I have seen the Leghorn Rooster mate w/her. Should I let her set to encourage the instinct? And what kind of chick would it be? There is only 1 egg under her right now. She shows no sign of leaving it. I'm new at this and wanting the Lg. white eggs from the Leghorn hens, which are a month younger than the EE chickens. I have 3 more EE chicks that have not started laying yet.