We Preach of Christ

2 Ne 25:23, 26

For as Nephi said, it seems that we labor diligently in the Church to bring are children and brethren unto Christ. The Church is not only preaching unto the world but also acting as a charity and relieving those in Africa or third world countries, or even in the states that are in need of assistance financially or physically.
As to pertaining of writing of Christ so our children will know, I think what it means by children is also meant by our posterity or our grandchildren. Our children and their children need to know what we stand for and how we acted righteously and in the Lord. That is one of the reasons why we are supposed to keep a journal of all our proceeding and events in our lives.