For all of you who have cats... how do they treat the chickens? Are they allowed outside with them? How and at what age did you introduce them? My grandson wants a cat, his dad's allergic so they can't have one at their house and he wants me to get one - ut I already have 'his' three chickens! Need some advice on if I should get one. I'd like it to be an indoor/outdoor cat. (the house came with a cat door...LOL). Thanks!