Father tonsured Mara by cutting her hair in the shape of the cross. He called this her gift of thanksgiving for what she had just received.

A brief explanation of tonsuring taken from HERE:
Our first STEWARDSHIP offering comes during our Baptism. In thanksgiving for the gift of new life in Christ, we make a personal sacrifice. The tonsuring of the hair is a symbol that we give a part of ourselves to God. This act of the newly baptized member of the Church is done freely and cheerfully. By this act we declare that we will not only offer a part of ourselves to God, but will commit our whole life to Him!