Yes, this sounds very similiar to Navajo kinship. The Navajo also have very strict taboos, far stricter than western taboos. Instead of tracking down distant relationships, they use a clan system. The primary clan comes from the mother. So, the mother's clan becomes a child's primary clan and the father's primary clan (which he "inherits" from his mother), is the child's secondary clan. In the case of my daughter, she is half navajo with me as her mother being non-Navajo. If I was Navajo, my clan would be her primary clan. Because I am not, her primary clan is her father's mother's clan (Tl'izilani--Many Goats) and the secondary clan is her father's secondary clan as well (Nakaii dine'e--Spanish or Mexican people, depending on who you ask). It is absolutely forbidden to marry anyone within your same clan, even if a direct kin relationship cannot be discovered. So, if two people both have the same primary clan, it doesn't matter if they are fourth cousins or that no relationship can be established--they are family, period. This is very serious with the primary clan and only a little less severe for the secondary clan. To marry somebody of the same clan will incur excommunication from the tribe.

A funny story. One of my husband's Navajo coworkers developed a crush on their female Navajo coworker. He stumbled over himself every day. One day, they were all driving out to a remote location to switch out some equipment at a pop and the topic of clans came up. The smitten coworker soon discovered the most dreadful thing that he could--he and this woman have the same clans, both primary and secondary. He might as well have had a crush on his sister--it was that bad. lol Needless to say, he treats her like a big brother now.

It gets really confusing here for me sometimes. My daughter (and my son who is "adopted" in as well by my marriage) has probably 20-30 aunts and uncles and about the same number of grandparents, lol. My husband's aunts are his aunts but they are like grandmothers to my daughter. Thankfully, I don't have to remember this extended relationships as you do. I'd be in big trouble if I did, hee hee.

Stephanie

In every man there is something wherein I may learn of him, and in that I am his pupil.--Ralph Waldo Emerson