Sesqui-cousin or sesqui-1C:
1- Child of their parent’s full sibling with the other parent’s half-sibling.
2- Person who, in relation to the other person, has zero parents and three grandparents in common.
1- Child of their parent’s full sibling with the other parent’s half-sibling.
2- Person who, in relation to the other person, has zero parents and three grandparents in common.
My sesqui-first-cousin is a good person.
by Gerald128 May 15, 2021
Get the sesqui-first-cousinmug. 
1- Stepcousin's child.
2- Stepgrandpibling's child.
3- Grandpibling's stepchild.
4- Cousin's stepchild.
2- Stepgrandpibling's child.
3- Grandpibling's stepchild.
4- Cousin's stepchild.
My step-1C1R is a good person.
by Gerald128 April 07, 2021
Get the step-1C1Rmug. Sesqui-3C:
Person who, in relation to the other person, has zero parents, zero grandparents, zero great-grandparents and three great-great-grandparents in common.
Person who, in relation to the other person, has zero parents, zero grandparents, zero great-grandparents and three great-great-grandparents in common.
My sesqui-third-cousin is a good person.
by Gerald128 May 17, 2021
Get the sesqui-third-cousinmug. 
My stepcousin is a good person.
by Gerald128 April 07, 2021
Get the stepcousinmug. Double-3C:
Person who, in relation to the other person, has zero parents, zero grandparents, zero great-grandparents and four great-great-grandparents in common.
Person who, in relation to the other person, has zero parents, zero grandparents, zero great-grandparents and four great-great-grandparents in common.
My double-third-cousin is a good person.
by Gerald128 May 17, 2021
Get the double-third-cousinmug.