The Charter is valuable spiritual reading for all Catholics. While recommended to all, it is a MUST for all families in Fatima Family groups. It explains the call to holiness of individuals and families which was given by heaven at Fatima. Preface by the Cardinal President of the Pontifical Council for the Family.
You can see a summary here. The Fatima Family Charter is necessary to form small apostolic groups for children, teenagers, young adults and Married Marian Couples or mixed groups of various ages.