The Fifth Summer (by Titia Sutherland)

(Amazon UK link) It’s a long time since I read the novels by Titia Sutherland. I recalled enjoying them, but not much else about them. So I decided to reread them, in the order in which she wrote them. It’s over twenty years since I read ‘The fifth summer’, and I had entirely forgotten the people and the storyline. 
The main characters are a family of four: Will and Lorna have been contentedly married for a long time, and have two teenage children. Debbie is eighteen, Fergus is sixteen. For the pa...