Sorry you lost your baby girl. Thing about all the praise of free ranging and all its many benefits, often times in all the glitter and excitement people forget (I'm guilty) that with free ranging birds you will eventually pay the 'wildlife tax'. Predators will keep returning regardless of your dog, they will learn it can't chase them away. Really with coyotes, its two things..'accessibility and opportunity'. You take those away and your birds will be much more safe. I live in New Hampshire so coyotes are a thing, but just one of many. Owls, hawks, weasels, fisher cats, foxes, possums, bears...every pen I build is wall to wall hardware cloth or fencing panels with a 1' curtain around the base to include the coop to prevent digging under. Good luck with everything.