Taking a salary from a person who took out an interest-bearing loan

Q: I am a student. I teach my aunts son mathematics. This is my first job as a student. I always wanted to earn halaal or I have a wish that my first salary or income will be atleast halaal.

My question is, somehow, I know that my aunts source of income comes from riba or a bank loan or something or fraudness which is haraam. Is my salary halaal or haraam? I am confused. Please explain, if it is not halaal then I will teach him for free. 

Advising a friend who is involved in a haraam relationship

Q: My friends brother is currently in a rehab. She was very close to him and she's finding it very hard. Shes in a haraam relationship due to this. I tried advising her but she said that it keeps her mind of her brother and that she doesn't know how to end the relationship. She feels that someone else will be able to fill the gap her brother left behind. What advice should I give her?