One of the most frequently and consistently asked questions concerning family structure is about understanding cousin relationships and identification. Key to this understanding of cousin relationship titles is to first establishing who the first common ancestor is. All relationships measurement begins at a common ancestor, and the first common ancestor that all 1st cousins have in common is grandparents (2nd Cousins is great-grandparents and 3rd cousins is great-great-grandparents etc).

Prerequisite for having a 1st cousin is having an aunt or uncle with children. If your parent was an only child or had a sibling who did not have children… No 1st cousins for you! You may still have 1st cousins once removed or twice removed, etc. but no first (full) cousins.

If your grand parent(s) had siblings who had children…, the closest cousins you would have are first cousins once removed.

Examples:

1. If the first common ancestor is grandparent then your relationship is 1st cousin. If the first common ancestor is mother or father then your relationship is sibling!
2.  If the 1st common ancestor is the parent of grandparents then your relationship is 2nd cousins.
3. Lastly… Examples 1, 2, are of persons who are the same generation. When the generations (distance from the common ancestor) is the same, the relationship is always a whole number (i.e. 1st cousin, 2nd cousin, etc.). When there is a generational difference (i.e. the comparison is between a 1st cousin of your parent and you), then the result is a 1st cousin once removed. If the comparison is between your grandparents first cousin and you, the result would be First cousin twice removed.
   Don’t be confused about 2nd or 3rd or 4th, ect., cousins! A second cousin is simply a person who both persons have as the first common ancestor great grand parents, and third cousins would have great-great-grandparents in common.
   Not so tuff!

Use the charts below and play with it for a bit and you’ll get it!