Recently my wife Jennifer facilitated and all day workshop at The Harbor called Gospel-Centered Parenting. In preparation for the event, this was one of the books we read and used to shape the day's messages.
Give Them Grace primarily addresses the role of the gospel in our lives as parents. As the authors point out, the Bible has less to say directly about parenting then all the Christian books on parenting would leave us to believe. Indeed, in the New Testament, there are only two verses that specifically address how we as parents should parent. However, the Bible does have a lot to say about the gospel and how our understanding of the gospel should influence every area of our lives - including our parenting.
As such, the first third of the book the authors lay the foundation for the book by explaining and clarifying the reader's understanding of the gospel. When you understand that God is sovereign and His grace is unconditional, then you as a Christian parent can and should feel the freedom that truth offers. It's not on you to get your kid to follow and love Jesus.
The strength of this book was in the way the authors constantly apply and illustrate the gospel in the context of Parenting. They show that if our parenting is to be truly 'Christian' then that approach should look radically different than the way mormons, muslims, and moralistic atheists parent their children - the difference is our understanding, proclamation, celebration of the gospel within our family context. Our goal as parents is not to produce nice little pharisees we can be proud of. Our goal is to delight in our Savior and consistently speak of and point out the wonders of God, His grace, and His love.