Confirmation

Among the faithful of the Catholic Church there is a clear boundary between children and adults. While baptism is administered early on in life, being considered essential for the salvation of any soul. The child in question is usually too young to make the necessary promises, and so such promises are made on their behalf by their parents or Godparents.
Once a child has achieved the age of reason (generally about 7 or 8 years old). They are considered mature enough to know the difference between right and wrong, and so ready to begin preparation for full membership within The Church. The first step in this process is preperation for and receiving for the first time, the sacraments of Reconciliation and Holy Eucharist. This order is specific to children and was established by Pope Bl. Pius X some twenty years ago. This process involves first catechising (that is teaching) the child in the faith and through the sacraments giving them the grace necessary for life as full members of The Church. When this is done there remains the last Sacrament of Initiation that is granted to all members of The Church upon entry to it.
The Rite of Confirmation is one of the most solemn within the Church. Performed at the Easter Vigil for adults, and Eastertide and Pentecost for children, it marks a persons full entry into The Church and Society of Christians. Before hand the person to be confirmed (confirmandus) will choose a saint as a personal patron to guide them and intercede for them before God. In this rite mass is said (as is usually the case) though between the liturgies of The Word and The Eucharist the celebrant (the local bishop if possible), addressing the confirmandus by the name of their chosen patron, anoints the confirmandus with the holy oil of Chrism and calls down the Holy Spirit to fill the child and impart his gifts upon them. It is for this reason that the hymn "Veni Creator" often sung at Pentecost, is used frequently at this celebration. 
Chrism is one of the three Holy Oils, distinguished from the other two by blessings used upon it and being mixed with balsam rather than pure olive oil. Also used at the ordination of deacons, priests, and bishops, as well as the coronations of monarchs. This oil is used to invoke the Holy Spirit and as a sign of a change, invisible from the outside, but very much real, taking place within the soul of the person so anointed. Thus is a person transformed by this sacrament. As they are by any other, though in a way particular to this one. The person so anointed is now considered a full grown member of The Church and Christian. What lays in the future for such people only God knows. However those who receive this sacrament worthily will prosper greatly by it. In their character and virtue, despite whatever sufferings await.