Is there a word or phrase to describe all familial relatives who are a part of the same family tree, but not either direct ancestors or direct descendants?
Included in that list would be:
- siblings
- siblings of parents (aunts/uncles)
- siblings of other ancestors (great-aunts/uncles, etc)
- children and descendants of the above (cousins, nieces/nephews, etc)
The term collateral descendant appears to cover a subset of that group, but not the descendants of ancestors not in the same direct line, such as aunts/uncles.