Question Summary:
My son inlaw spares no effort to ridicule my daughter, He abuses her and has even beaten her badly. All this he tells is in his fit of anger… what prayers will help him, and releive my daughter of her plight…

Question Detail:

My son inlaw spares no effort to ridicule my daughter, He abuses her and has even beaten her badly. All this he tells is in his fit of anger... what prayers will help him, and releive my daughter of her plight

Answer :

In the name of Allah, Most Gracious, Most Merciful
Assalaamu `alaykum waRahmatullahi Wabarakatoh
His ‘fit of anger’ excuse is merely a ploy in justification of his abusive behaviour. If you are around, would he still stoop to such despicable behaviour even if he is gripped with fury? No. So this anger can be controlled. Regardless, this is no excuse to abuse her. Rather, get the other senior members on a local religious body involved in an attempt to resolve this situation. 
Recite the following duaa repeatedly.
“Rabbi Inni Maghloobun Fantasir” (Surah Qamar, verse 10)
Also, continue making duaa for both of them. 
And Allah knows best
Wassalam
Mufti Ebrahim Desai
Darul Iftaa, Madrassah In'aamiyyah