Dear son John,
This is your dad talking to you through this letter. There are certain things which I need to convey you and I felt this letter shall serve my purpose. John, you have been a prized possession of this family and especially mine and will continue to be so forever no matter what may come. However, you need to prove yourself for the outer world and make yourself, and us, proud. You have always been course for such an ideal life.
However, in the recent times, my concern in this regard has mounted. You have been going astray of the aim which you have set for yourself and even your behaviour with other family members has not been the same. I know these adolescent days; but these are the cementing days for your life and career. I appeal you to think in this regard and act according to what you think is reasonable.
Yours caringly,
Dad [Peter]