Women harrasement

Respected Sir/Madam My elder sister was appointed as a Receptionist by third party in Public Sector undertaking 3 years ago. All was well in first year. In 2nd year CMD of such public undertaking called and used non scence words like tum 'buhut aachhi lagti ho' looking hot etand insisting for tour along with him He ask her to come on Saturday/sunday without any work. He was frequently sent whatapp to her 'looking pretty, etc. etc. He was insisting to sit late around 8.00 - 9.00 p.m. without any conveyance or over time He said 'Aap ko Company me aana hai to open mind hono hoga etc. etc. i we have available sufficient proof of bio-metric records for late sitting with this kind of tactics been adopted by him my sister got mentally harassed and she has resigned from her duty on 31st July,2017. she is now Doctor's observation. My father working in same organisation Kindly advice us the appropriate action/step against him. what action he should taken against my father after FIR