Depends on the anthropologist, era, and what culture/society they are talking about. Some societies don't have strictly distinct relationships between family/extendedfamily/tribe, and some have vert strict hierarchies within extended families that create the traditional idea of 'clans'.

Early structuralists were very keen on creating the distinction between 'kin-groups and tribes', but it stopped being in vogue around the 1960's. Still important work, but not considered as 'essential to understanding the development of civilization from the Platonic model'.

The issue is that it can get messy pretty quickly, because the whole idea of strictly genetic family relations comes mostly out of herding cultures, whereas other cultures, especially hunter-gatherers, had traditions like, "When you are with us, your name is Jon, who was my grandfather, which means you are my grandfather and that you have the obligation/privilege to take care of my family if something happens to me". Which means that when the anthropologist comes around you call that dude "Jon, my grandfather" even though he is clearly the same age or even younger than you, and maybe married/sleeping with your daughter and the anthropologist has to care enough to figure out what is actually going on.