You may visit the website of Ministry of Personnel,PG & Pensions of Govt of India and elicit the information by consulting the provisions under Civil Services (Conduct) Rules 1964- its additions. amendments etc fromtime to time. If necessary their RTI site also may be visited for any querying in future.
As far as I can recollect- Certainly there are stipulations and preconditions for association of the Govt. servants/ their relatiuves with NGOs- and also there may be some total restrictions on any type of dealings with activities of the NGO.
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