I have a teenage girl (fifteen years old, to be exact) whose father passes away from morphine overdose and whose mother committed suicide about ten years before. Now, she doesn’t have any living grandparents or siblings. The only accessible relatives she has are her aunt and cousin, and while it was her father’s wish that she be left to her aunt if anything were to happen, she’s bedridden from arthritis most of the time and can’t take care of the girl in question.
Her cousin is twenty-six years old, single, and makes a decent living. This said, would it be plausible for the girl to be placed under her cousin’s care? What level of involvement would the law have with this?
Search terms used: “nonparental custody” “custody laws in washington” “third party custody” “custody of children when both parents are dead” (Needless to say, they provided vague information and not the type I'm looking for)
ETA: I can't believe I forgot to add this, but the fact that the father wanted the girl to stay with her aunt was explicitly written in his will.