Making dua for a friend

Q: I have a very close friend of mine. Due to some personal reasons, I am feeling like as if someone has done some magic on her. I wanted to ask about some dua as told by Nabi (Sallallahu Alayhi Wasallam) or mentioned in Quran to get a solution for it. Furthermore, I wanted to know whether it is alright to recite this dua even if we doubt that somebody is under the influence of magic? I wanted to confirm this.

Dyeing the hair

Q: I had confusion in hair colouring. I am twenty years old and I have slight brown hairs which I want to dye and turn it into fully brown colour hairs. Please let me know if it is permissible?

Living with one's wife abroad

Q: I am working abroad and I would like to call my wife here. My father passed away and I have four younger brothers in the house with my mother and wife. All brothers are studying. My wife takes care of all. I can't stay here without my wife. I need her mentally and physically. In this case if I bring her here, will it cut off my mother's rights and will Allah be angry with me? What will be the Shar'ee hukm regarding this?