I truly recommend the book called "The Wondrous Childhood of the Most Holy Mother of God" by St. John Eudes. He was a Catholic priest from France, ordained on Dec. 20, 1625. He was the author of the proper for the Mass and Divine Office of the Sacred Hearts of Jesus Christ and the Blessed Virgin. The Sacred Heart of Jesus, is the same heart as Mary. He lived during the time of St. Margaret Mary Alacoque, who told King Louis XIV to consecrate France to His Sacred Heart but he didn't do it until it was too late, with the French Revolution.
The book is about the incalculable graces and merits of Mary, from the moment of her Immaculate Conception. Her graces doubled from moment to moment. It also speaks about how Mary, at the age of three, went to the Temple and stayed there. This true event can be seen in the old testament with baby Samuel. His mother's name was Anna, and she was barren for a long time, just like St. Anne, Mary's mother. She asked God and promised if she could have a son, that she promised that she would dedicate [give] her son to God and the Temple at the age of three.
1 Kings [1 Samuel] 1:2, 11, 20, 24, 26-28 And he had two wives, the name of one was Anna, and the name of the other Phenenna. Phenenna had children: but Anna had no children. … And she made a vow, saying: O Lord, of hosts, if thou wilt look down on the affliction of thy servant, and wilt be mindful of me, and not forget thy handmaid, and wilt give to thy servant a man child: I will give him to the Lord all the days of his life, and no razor shall come upon his head. … And it came to pass when the time was come about, Anna conceived and bore a son, and called his name Samuel: because she had asked him of the Lord. … And after she had weaned him, she carried him with her, with three calves, and three bushels of flour, and a bottle of wine, and she brought him to the house of the Lord in Silo. Now the child was as yet very young: … And Anna said: I beseech thee, my lord, as thy soul liveth, my lord: I am that woman who stood before thee here praying to the Lord. For this child did I pray, and the Lord hath granted me my petition, which I asked of him. Therefore I also have lent him to the Lord all the days of his life, he shall be lent to the Lord.
For myself, I wish I was brought up learning and saying the Rosary, at the age of three. How very different my life would have been! Please read this book, if you love Mary, you will not be disappointed!