That's the Catholic argument.
That may be the Catholic argument but it's unsupported by Scripture.
There's nothing in Scripture that indicates Mary was inherently anything special over against anyone else. She was a sinner, just like the rest of mankind, and she had a normal marriage with Joseph who the Holy spirit TOLD to take as his wife.
They had a normal, God honoring marriage which included sex and children. The names of the boys are even listed for us.
[41] And it came to pass, that when Elizabeth heard the salutation of Mary, the infant leaped in her womb. And Elizabeth was filled with the Holy Ghost: [42] And she cried out with a loud voice, and said: Blessed art thou among women, and blessed is the fruit of thy womb. [43] And whence is this to me, that the mother of my Lord should come to me? [44] For behold as soon as the voice of thy salutation sounded in my ears, the infant in my womb leaped for joy. [45] And blessed art thou that hast believed, because those things shall be accomplished that were spoken to thee by the Lord.
[46] And Mary said: My soul doth magnify the Lord. [47] And my spirit hath rejoiced in God my Saviour. [48] Because he hath regarded the humility of his handmaid; for behold from henceforth all generations shall call me blessed. [49] Because he that is mighty, hath done great things to me; and holy is his name. [50] And his mercy is from generation unto generations, to them that fear him. Luke Chapter 1
Did Luther yank the above out your "bible"?