I wonder if the young couple you mention were the excellent Dave Shannon and Fiona Simpson who performed as the duo Therapy in Folk Clubs from the early 1970s. The song Killaloo.. appears on one of their albums .. I still have a signed vinyl copy .. as part of a "live" section on the album. They performed the song so well ... and it was always very well received. I saw them perform numerous times ... always a packed house whereve they performed, and this song was often requested.

Sadly Dave passed away a few years ago ... and the music community lost a very talented musician and comedian .. and a great bloke!