CCC 501 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.”1
1 LG 63; cf. Jn 19:26-27; Rom 8:29; Rev 12:17.