Yes, recently, I had replied that Family pension to unmarried daughter of more than 25 years age is permissible.
However, please note that the Office Memorandum No. 1/19/03-P&PW (E) dated 6th September 2007, mentioned in the above reply was issued by the Government of India, Ministry of Personnel, P.G. & Pension, Department of Pension & Pensioners’ Welfare. It would apply in the case of Central Government employees. In your question, you have not clarified under which Government your father was working. If he retired from the Central Government, then your sister may be eligible. But, if your father was working in some other Government or some other organisation, then you’ll have to check the relevant rules applicable in that Government or organisation.
If your sister fulfils the conditions mentioned in the above circular, then you may have to the contact the authority in the concerned department which had issued the orders for family pension to your sister, and bring to the knowledge of the said authority the directions of the Government of India in this regard. If they ask you to complete certain formalities, like giving proof of your sister being unmarried, then please submit such proof as per the format required by them (such as by affidavit or as per their requirements).
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