Lynne Perrie(Billy's mother) and Duggie Brown(the milkman) were brother and sister in real life.
Interesting :)"Nobody is free, even the birds are chained to the sky" - Bob Dylan
and both appeared in Coronation Street as I recall
They both also appeared in an episode of Play for Today (Leeds - United!) ... written by Colin Welland (the sympathetic teacher, Mr. Farthing)