I have sole legal and physical custody of my 3 year old son. I wanted to see if anyone here has any knowledge on what I can do (if anything) to appoint a guardian for him, other than his BD, if something were to happen to me? I would like to appoint my sister, but I don't know if there is anything I can do legally to make it so that she would get custody of DS rather than his father? Do parental rights trump any legal document I may have written up? Even if I have sole legal custody?