registration of grand father's property to third party by his son

my grand father registered his own acquired property to my father,who adopted me at the age of eight years,and after the death of my grand father,my father who adopted me had soled out and registered the property to another party who is not related to our family,he soled out the property with out my concern even though i am a major,is that registered sale valid without my concern,as the property when he was selling i was already a major, and as my adopted father left me without any thing to me,he died by enjoying the money he got by selling my grandfather's property,can i get that back.