Help! Please!

[drkangel008]

My father passed away today. He lived with his mother for five years. He was in ICU for eight days, While he was in the hospital, all medical decisions were made by my older sister. There is no wife, and there was no written will, the only thing that anyone is going on is word of mouth. My grandmother is saying one thing, and my sisters and I are saying something else. My concern is that she has his disability checks, and we don't have access to any of that. She also has all of his belongings which isn't much. It consists of a tv, a computer, and clothes. He didn't own anything of real value, but he was very proud of what little he did have.I'm going to say that in all the value of what he does have is maybe around $1000 or less. My grandmother is also claiming that she bought all his stuff so it all belongs to her. So what my question is, in this case, is who has the rights to his belongings, would it be the person he lived with, or my older sister, who is considered, and has been considered for over a month now, the next of kin?