Keeping a dog aggressive dog separate is very hard work and requires that you constantly know where everyone is. I do it with two of my dogs. Kayleigh hates everyone, so she's actually a little easier. Goldie is selectively aggressive. So I have to make sure she doesn't get near the dogs she hates. I also have to make sure that my husband and any one else who is around knows that when Goldie is loose or in the house, the dogs she dislikes must be elsewhere. It's constant work, but it can be done. Life can still be happy, fun & safe for all the dogs. You would need to get a committment from everyone in your house though that they would follow the same rules.

IF you decide to rehome Ziggy, you need to be extremely careful that her new owners are fully informed. If you moved her and didn't inform them of her aggressive tendancies, you could be held liable if she attacked again. A one dog home solves nothing if they let her off leash and/or don't monitor her interactions with other animals.

Has Ziggy ever bitten a person?