My greatgrandma has unclaimed cash. She is perished. Her folks are perished. Her mate is perished. Her lone kid is perished. She had 5 grandkids, and I am one of 18 incredible grandkids. Who is the legitimate successor to guarantee the cash?

My greatgrandma has unclaimed cash. She is perished. Her folks are perished. Her mate is perished. Her lone kid is perished. She had 5 grandkids, and I am one of 18 incredible grandkids. Who is the legitimate successor to guarantee the cash?