To go back to Brian's post about the 'backstory' for singer's versions of their songs -- I'm not sure that there was any explanation behind Jeannie Robertson's version of 'Son David', but I am sure that it was a very significant song for her, because her only son had died young, so her memory of loss was very strong. (Apologies for not taking the time to check this just now, but will do later, and if there's any further info. - I'll post it.)
Before I go, you might be interested to hear that Gordeanna McCulloch and myself did the first of three ballad workshops in Glasgow this afternoon - not part of Celtic Connections - and had 23 hardworking participants, between one third and one half of whom were ballad novices. All were enthusiastic and some were passionate, which confirms my belief that there is a real audience out there for these songs.