As Mike says the song is not literally about Bob Cooney because Ian Campbell wanted it to be a song fitting in the wars of the twentieth century so Bob was too young. But Bob lived with the Campbell's as well as being a long time friend they knew from Aberdeen from before the SCW. I think he is bound to have been a major inspiration for the song, but it would good to get the full S.P. from Ian Campbell - anyone? I have heard a tape of Bob himself singing the The Old Man's Song.
The Mudcat Thread About Bob Cooney