Empty nesters are a demographic segment that represents middle aged or older couples who are no longer living with their children or couple whose children have established a household of their own.
The parents hence stay away from their children in a separate house as their children has established their home elsewhere where they are studying, working or married.
Mr and Mrs Raman raised 2 children who have become self dependent and are living in a separate house along with their families.
So, as empty nesters Mr. and Mrs. Raman no longer need the duplex flat in which they are living now. Thus they would look for a smaller 2 room flat which would be sufficient enough for them.
Empty nesters are an important segment for many industries including small house industry.