A man has raped a woman and she gave birth to a baby boy. To whom should that baby be attributed?
All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
First of all, the adulterer must be punished according to the rules of Sharia and the baby isn`t attributed to him. Rather, it is attributed to the mother. This adulterer has committed a grave sin and incurred the wrath of Allah. We advise him to make sincere repentance to Allah and pray that Allah forgives him. And Allah The Almighty Knows Best.
Is it permissible for a financially capable woman to pay the Zakat to her sons or one of them?
It is permissible for a mother to give her children from zakat if they are eligible to receive it, even though she is obligated to provide for them. This is based on the saying of the Prophet Muhammad (PBUH) regarding Zainab, the wife of Abdullah Ibn Mas'ud (may Allah be pleased with them): "Your husband and your children are more deserving of your charity" [Al-Bukhari]. And Allah Knows Best.
What is the ruling on determining the sex of the baby whether through killing the female spermatozoa, or any other way in order to have a male?
If it is done through having a certain type of food, taking a certain type of medication, or organizing the time of the marital relation, then it is permissible.
What is the ruling on giving Zakah (obligatory charity) to one`s relatives?
It is impermissible to pay Zakah to one`s origins (parents and grandparents) because providing for them is an obligation on their branches (sons and daughters) if they were poor, but it is permissible to give some of the Zakah money to relatives whose provision isn`t due on the giver of the Zakah.