Proto-Kui-Kuwi : *kūk-
Meaning : to shout, coo
Kui : kūpka (<kūkp-; kūkt-) "to shout, hail, call aloud"
Kuwi (Schulze) : kuperi potha "cuckoo"
Notes : If -p- here is indeed ancient (from *kuk-p-eri), preserved before a vowel, the comparison may be justified.
Number in DED : 1868