Q:
1. What are the requirements of a valid marriage in Islam? Is the consent of parents mandatory?
2. If a girl and boy (both adults), in the presence of two adult male witnesses and without the consent of their parents, performed Ijaab and Qabool (without any duress and with free will), is this nikah valid?
3. If the answer to question 2 is 'yes' and if the parents of both the girl and the boy agree for their marriage in future without being aware that the girl and boy have already entered into nikah, (and the girl and boy do not want to reveal this fact to their parents), can they enter into nikah again when the marriage takes place for the purposes of registration in union council?