My Brother-in-Law got Married to a Girl, After 3 days without any reason and (No Sexual Relations) she left home with all the Jewellery and cash of both sides given to her and never came back. Now they are harassing us to pay all the money they spent on marriage. What should we do now, we want only justice and if there is any possibility of null and void of marriage.

First its not a good idea to piggyback your question on another thread. This can lead to confusion. So I've moved your question to its own thread.

Who is the they that is harassing him? How long ago did this happen and where did it happen (ANY question on law needs to include your general locale as laws vary by area. )

He should be report this to the police and apply, in Family Court, for an annulment which should not be a problem in getting. However, any debts he incurred as part of the wedding are still owed.

If she is the one who ran away, why is HER family demanding money? I don't understand. Did she run back to them claiming cruelty? If she just disappeared, I would think your brother in law would be suing her family. (If this is India, for example.)

My Brother-in-Law got Married to a Girl, After 3 days without any reason and (No Sexual Relations) she left home with all the Jewellery and cash of both sides given to her and never came back. Now they are harassing us to pay all the money they spent on marriage. What should we do now, we want only justice and if there is any possibility of null and void of marriage.

As I understand this, wedding gifts were received by the married couple, with which gifts the bride ran off. The persons who gave the gifts are harassing the family of the groom?

I don't believe you are responsible to return wedding gifts. The fact that the bride ran away is unfortunate, but not grounds for a lawsuit. If, as Joypulv asks, this is in some exotic land, the laws thereof with which I am unfamiliar, I wouldn't mind being corrected.