There was also a reply from Rollo that seems to have disappeared. (Thanks R, if you haven't thrown your computer out of the window in frustration!) He suggested 'forking', which meets the 'parting' criterion, on the grounds of 'for' meaning 'supporting' and 'king' relating to Romeo.
I'd thought of 'kin' meaning 'family' but couldn't relate 'g' to 'Romeo'.
If you have solved the other thematic clues then you will realise that this another of them. "The weather outside" in this case is FOG with R for Romeo and kin on the inside., and also meaning "parting"
Does that mean that the rest of the "thematic statement" is used somewhere? "Oh, the weather outside is frightful".
I thought family was the superfluous word supplying the last f in the song quotation.