What do knee and generation have in common?

It occurred to me that the words pokolení (generation) in Czech (and pokolenie in Polish, поколение in Russian, etc.) and koleno (knee) in Czech (and kolano in Polish, колено in Russian, etc.) might be related, just like the Modern Greek word γενιά (generation) (pronounced yeniá in Greek) is related to γόνυ (knee) (pronounced γóni in Modern Greek) and the Latin generatio (generatio) and genu (knee). It all comes down to words like genesis, beginning, and Greek γονeίς (pronounced γonís), meaning parents. More here.

My Czech etymology dictionary, though, states that pokolení {generace; rod}. Všesl. - p. pokolenie, r. koléno, ch. pokoljénje. Nelze oddělovat od slova koleno, prý podle pradávného zvyku, kdy stařešina rodu bral novorozeně na kolena a tím je uznal za příslušníka rodu. V ie. jsou si skutečně názvy pro {koleno} a {rod, rodit} velmi podobné (srov. lat. genus {rod}, genū {koleno}), ale oba kořeny se obvykle považují za homonymní, which roughly means that no derivation can be obtained from koleno (knee), a folk etymology according to which an old woman of the family, tribe or clan would grap the newborn by the knee and would thus recognize him or her as a member of the tribe.