I will add more to the story so you will understand it better.
Please understand that this was a stray cat that she took in to care for the abscess he had. He went crazy when she tried to keep him in, so she had to let him out so he wouldn't harm her cats at the time as he would attack them, not viciously, but enough to make her worry for her cats.
She figured maybe he wanted to get back home, but he would come back at night. She made a shelter for him. My sister kept pleading with the hubby to keep him to no avail. When no one claimed him after about three weeks, she found another home for him. That didn't work out, the woman brought him back last Tuesday. She kept him in the basement that night and talked with hubby again and he agreed to give it a try. Wednesday morning, she put her cats in a room and let the cat out of the basement. Right away he went to the door crying like mad to go out. So she let him out as she figured once they brought him to the vet to be fixed he would settle down and they didn't see him until last night. They were going to bring him to the vet to-day to get him checked out, vaccinated and neutered. He will now remain an inside cat and will be slowly introduced to her two cats.
I guess next time I shouldn't shorten a story.