In Mosiah 10:11-17 we learn about the importance of family history. The Lamanites had spent years hating the Nephites because of misunderstandings in their family history, and because of this, the following generations were influenced to make wrong decisions.
Mosiah 10:11 and 17
11: Now, the Lamanites knew nothing concerning the Lord, nor the strength of the Lord, therefore they depended upon their own strength. Yet they were a strong people, as to the strength of men.
17: And thus they have taught their children that they should hate them, and that they should murder them, and that they should rob and plunder them, and do all they could to destroy them; therefore they have an eternal hatred towards the children of Nephi.
It's important that we teach our children their family history. Studies have shown that when children know their family history and where they came from, they have a better sense of awareness of who they are, and can grow from those experiences of their ancestors.