Thank you very much. @SCSusila - Madam, if you are interested to read the same,I found that being listed here . Myself started reading it. @rgsrinivasan - 'Sarala' seems to be another story that involves two sisters. 'Akka' being the advisor instead of Amma. The story "IruKadithangal" of Sujata as @sweetsmiley posted has the 'Amma' character as Chemistry Lecturer writing letters to her only daughter Sumathy. Thank you all for kindling my interest.