I believe Martin and Sonia have a very strong relationship, this is the first major crisis in their marriage, apart from the stalker and Sonia forgave Martin even before she found out that nothing happened with Sarah which proved the strength of their love for one another. Their main problem so far has been living with Pauline, in fact they have been so loved up its weird to see them fight ! It will interesting to see what happens after they both see Chloe next Friday and how they cope afterward. Its complicated but I could'nt help thinking last night when I saw Chloe's elderly grandma , that Martin and Sonia should be a part of her life as her grandma won't be able to look after her forever and then her life will be disrupted again and she will find out when she is older that she was adopted and could resent her parents for not fighting for her. Whereas if she can now develop a relationship with Martin and Sonia when her grandma is no longer able to look after her , living with Martin and Sonia will seem natural to her. Chloe would still remain in contact with her extended adopted family. Ultimately its up to the executive producer but i really hope Martin and Sonia remain Mr and Mrs Fowler, i love the idea of them been the new Pauline and Arthur without the cardigans !