The Proto-Indo-European family tree. Interesting use of the same...

The Proto-Indo-European family tree. Interesting use of the same term for different family members, suggestive of an equivalent relationship/same importance being placed on those individuals? E.g. your brother’s son and your own son (Mallory, In Search of the Indo-Europeans).

Likewise, the maternal uncle and grandfather have the same title. The special relationship with the maternal uncle is well attested and was clearly as important, if not more so, as the relationship with grandfathers, despite descent from the latter.