Great-great-great-grandparent's brother.
My great-great-great-granduncle is a good person.
Great-great-great-grandparent's brother.
great-great-great-granduncle.
Great-great-grandparent's half-brother.
My half-great-great-granduncle is a good person.
Great-great-grandparent's half-brother.
half-great-great-granduncle.