Pension

Respected Sir/Madam, My friend's father was a Gr.-D employee of Govt. of West Bengal. Recently he expired. He was pension holder. Friend's mother also died earlier. Now, my friend's elder sister's husband is absconding for last 15 years. There is a general diary with police which they took 15 years ago. Can my friend's elder sister claim her father's pension now ? There is provision in Govt. of West Bengal that after parents (both) death unmarried, divorcee or widow daughter can claim any of parents' pension after their (both) death. How ? Please do advice. Thank you.