| Who is it? | Relationship to you | Common Ancestors |
| sibling of your grandparent | grandaunt or granduncle | your great grandparents |
| first cousin of your grandparent | first cousin twice removed | your great great grandparents |
| second cousin of your grandparent | second cousin twice removed | your great great great grandparents |
| third cousin of your grandparent | third cousin twice removed | your great great great great grandparents |
| n-th cousin of your grandparent for n>3 | n-th cousin twice removed | your (n+1) times great grandparents |
Note that we could speak of zeroth cousins instead of siblings. A sibling relationship is exactly the same kind of relationship as is a cousin relationship. It's just that siblings are one generation closer than are first cousins. Similarly, an aunt or an uncle is a zeroth cousin once removed.