Answer
(Fatwa: 689/450/H=1432)
Dua is accepted more in tense conditions. You should behave your father with respect and politeness instead of his attitude. Recite Surah al-Quraish after each salah 7 times with durood 7-7 times before and after, blow it on water and mix it in tea, milk, soup, flour, and give it to your father to drink or eat. There is no problem if other people consume it. Also, you should make special dua for your father besides blowing it on water.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband