In a seminal text in the diachronic study of Oceanic languages, Malcolm Ross (1988:141,147) reports the sound change Proto-Oceanic *R > lk/_# in the language Kaiwa. A few lexical witnesses of this sound change are reported in that text, but otherwise it is not discussed in detail. Subsequent works that have mentioned Kaiwa have tended to implicitly reject the accuracy of this original claim or be ambivalent to it, but have continued to not address it in detail. This paper re-examines the literature discussing Kaiwa lexicon and phonology, provides some more apparent witnesses of this sound change, and ultimately concludes in favor of its historical veracity. The sound change is also discussed in the context of the wider history of Proto-Oceanic liquid phonemes in the Kaiwa lexicon, and we provide phonological motivation for the changes represented in this history.