Like "Moominpappa at Sea", the work is more somber in tone than previous books in the series, and it has been suggested that this is a direct result of the death of Jansson's mother, Signe Hammarsten-Jansson, during the year that it was written. Because of this, it has been described as being a "textbook on letting go, being a mature orphan, existing spiritually alone" and features a young orphan looking for a mother as one of its primary characters. Following this work, Jansson later stated that she "couldn't go back and find that happy Moominvalley again" and so decided to stop writing the Moomin books.