Animal Family

• Nephew: sister's son, brother's son, wife's brother's son, wife's sister's son, husband's brother's son, husband's sister's son
• Niece: sister's daughter, brother's daughter, wife's brother's daughter, wife's sister's daughter, husband's brother's daughter, husband's sister's daughter
When additional generations intervene (in other words, when one's collateral relatives belong to the same generation as one's grandparents or grandchildren), the prefixes "great-" or "grand-" modifies these terms. Also, as with grandparents and grandchildren, as more generations intervene the prefix becomes "great-grand-," adding an additional "great-" for each additional generation. Most collateral relatives have never had membership of the nuclear family of the members of one's own nuclear family.
• Cousin: the most classificatory term; the children of aunts or uncles. One can further distinguish cousins by degrees of collaterality and by generation. Two persons of the same generation who share a grandparent count as "first cousins" (one degree of collaterality); if they share a great-grandparent they count as "second cousins" (two degrees of collaterality) and so on. If two persons share an ancestor, one as a grandchild and the other as a great-grandchild of that individual, then the two descendants class as "first cousins once removed" (removed by one generation); if they shared ancestor figures as the grandparent of one individual and the great-great-grandparent of the other, the individuals class as "first cousins twice removed" (removed by two generations), and so on. Similarly, if they shared ancestor figures as the great-grandparent of one person and the great-great-grandparent of the other, the individuals class as "second cousins once removed". Hence one can refer to a "third cousin once removed upwards."