In Berber, the roughly corresponding distinction is in general limited to inalienable relations mediated through your parents, ie those that have an important role to play in determining your own social identity: thus father, mother, brother, uncle, aunt, etc. use a different possessive construction than other nouns. For these words, the bare form means "my _" - eg Siwi aṃṃa "my brother". To say "X's brother", you have to add a 3rd person possessive marker first - thus aṃṃa-s n X (brother-his of X) "X's brother". In contrast, for other nouns, including people outside this category - eg amdarrəs "teacher" - there's no 3rd person possessor: "X's teacher" would just be amdarrəs n X.
As widespread as it is, the notion of inalienability rests on an experience of the world that, although it would be immediately recognisable to most people anywhere any time, has been under increasing pressure in a modern context. High mobility - geographical and occupational - makes even parents a rather less meaningful determiner of your identity and position in society, let alone uncles or aunts or birthplaces. For a person who has spent life far from most relatives and with no very strong ties to them, the saying "friends are the real family" has a resonance to it which would seem bizarre to most people throughout history. The body and the brain remain more or less inalienable for life - organ transplants notwithstanding - but a few half-mad futurists like Moravec dream of changing even that. The point of inalienable possessions is not just that they happen to be inescapable but that they define your identity in a way you can't control. The spirit of this age resists such impositions on one's freedom - just ask Dr. Phil. But as Chomsky points out, blank slates don't get anywhere, and "creativity presupposes fixed structure".