↑ A Handbook of Germanic Etymology, V.Orel, Brill, Leiden Boston 2003, p.214
Etymology
Dialectal; either (1) a blend of synonyms kec + edh, or (2) a singularized plural of *kadh, from Proto-Albanian*kadza, from Proto-Indo-European*koǵʰos (compare Serbo-Croatian koza ‘goat’, Old English hēcen ‘kid’). Dialectal qith has been influenced by qengj (variants qingjth, qîgj) ‘lamb’.[1]. A possible relation with Germanic *kidją (cf. Old Norse kið(“kid”), Old High German kizzi(“id”)) has been proposed, although this remains doubtful[2].