This symbolic play is centred on a lady called Ellida. She is the daughter of a lighthouse-keeper, and grew up where the fjord met the open sea; she loves the sea. She is married to Doctor Wangel, a doctor in a small town in West Norway (in the mountains). He has two daughters (Bolette and Hilde) by his previous wife (widowed), and he and Ellida had a son who died as a baby. This put big strains on the marriage. Wangel, fearing for Ellidaâs mental health, has invited up Arnholm, Boletteâs former tutor and now the headmaster of a school, in hope that he can help Ellida. However, Arnholm thinks that it is Bolette waiting for him and he proposes. She agrees to marry her former teacher, because she sees this as her only opportunity to get out into the world.
Some years earlier Ellida was deeply in love and engaged to a sailor, but because he murdered his captain he had to escape. Nevertheless, he asked her to wait for him to come and fetch her. She tried to break the engagement but he had too great a hold over her. The sailor then returns all these years later to claim her. However she then has to choose between her love or her husband. Dr Wangel finally recognizes her freedom to choose since he understands that he has no other options. This goes in his favour as she then chooses him. The play ends with the sailor leaving and Ellida and Wangel taking up their lives together again.

Question: What puts a strain on their marriage? 
Answer: The death of their infant son
Alternative answer: Their child died in childbirth