Awww, thank God they were all rescued and your little precious found you. Lots of love can do a great deal to erase their sad memories of neglect and abuse.
My little boy was a rescue too. Not from the conditions you mention though. He was not wanted by his human's latest girlfriend.
So one day she gave him a bath, perfumed him, and then opened the back door so he could go outside and ultimately run away. Well, he followed his nose because he is a tracker breed. And her house was about fifty feet from a busy highway.
Thank God she let him out the back door. He found his way to our house and after arranging with his human for his adoption, he's been ours ever since.