What can I do?

It was 20 August thirteen years back. We came from Riyadh to spend 45 days here. I saw my husband distributing chocolates to everyone in my in-laws' house. He looked very happy. He told his beloved mother that he was tired of living abroad and this time he would stay back.
He did stay back, but not alive. Sleeping in the grave, he must have felt the humiliation and injustice done by his family to his wife and children. Yes, he should have felt it. My husband constructed a red two-storied house in north Shyamoli in his father's name. One fine morning, when my father in-law became paralysed, the family members transferred the whole property to their names. All our money earned in Riyadh was spent in constructing this house. Me and my husband literally carried bathroom fittings and decorations by hand all the way from Saudi Arabia for this house. On 27 August 1997, just 7 days after our arrival my husband died of a massive heart attack.
I tried to get justice in many ways, but unfortunately I could not retrieve this share of our property from the grip of my husband's family. Where is the law to protect the rights of my children?