Home WowThoughts Double cousins share all 4 grandparents. So theoretically you could have quadruple second cousins that share all 8 great-grandparents. 1 month ago 1 month ago WowThoughts Double cousins share all 4 grandparents. So theoretically you could have quadruple second cousins that share all 8 great-grandparents. by showerthoughts 1.4kviews 421 Double cousins share all 4 grandparents. So theoretically you could have quadruple second cousins that share all 8 great-grandparents. Post PaginationPrevious PostPreviousNext PostNext Like it? Share with your friends! 421 Previous Post Every warm object I've ever held was liquid cooled by... by showerthoughts Next Post There's a bunch of wild animals we've never selectively bred.... by showerthoughts