I got some week-old Australorps today (a baker's dozen!), and my kids are absolutely smitten! We love holding them and hearing their chirps! How soon does my husband need to get that coop built?! Also, is it possible to transition them from the Starter/Grower Crumble to 100% real food? I've seen recipes for homemade chicken feed, but that's for full-grown chickens.... when are they full grown? Thanks!