sesqui-first cousin

Child of their parent’s half-sibling with the other parent’s full sibling.

My sesqui-first cousin is a good person.

sesqui-first-cousin

1- Child of parent’s full sister and of other parent’s half-brother at the same time.
2- Child of parent’s full brother and of other parent’s half-sister at the same time.
3- Person who, in relation to the other person, has zero parents and three grandparents in common.
4- Sesqui-cousin.
5- Sesqui-1C.

My sesqui-first-cousin is a good person.

half-cousin-nephew

Half-first cousin's son.

My half-cousin-nephew is a good person.

double-first great-cousin-pibling

Child of their great-grandparent’s full sibling with the other great-grandparent’s full sibling.

My double-first great-cousin-pibling is a good person.

half-great-cousin-uncle

Grandparent’s male half-first cousin.

My half-great-cousin-uncle is a good person.

irregular-tredecuple-fourth-cousin

Someone who, in relation to others, has zero parents, zero grandparents, zero great-grandparents, zero great-great-grandparents and twenty-five great-great-great-grandparents in common.

Irregular-tredecuple-fourth-cousin.

fifth-cousin-6X-removed

Fifth-cousin-six-times-removed (5C6R).

My fifth-cousin-6X-removed is a good person.