§501
Creed › … › Paragraph 2. "Conceived by the Power of the Holy Spirit and Born of the Virgin Mary"
Mary - "ever-virgin"
Jesus is Mary's only son, but her spiritual motherhood extends to all men whom indeed he came to save: "The Son whom she brought forth is he whom God placed as the first-born among many brethren, that is, the faithful in whose generation and formation she co-operates with a mother's love."
Source: Catechism of the Catholic Church (Vatican.va)