I do not debate the fact, that Mary was a Virgin UNTIL AFTER she brought forth her FIRSTBORN son.
(Matthew 1:24-25 KJV) "Then Joseph being raised from sleep did as the angel of the Lord had bidden him, and took unto him his wife: {25} And knew her not till she had brought forth her firstborn son: and he called his name JESUS."
Then Joseph "KNEW" her and she bore James, Joses, Juda, Simon, and his sisters.
(Matthew 12:46-47 KJV) "While he yet talked to the people, behold, his mother and his brethren stood without, desiring to speak with him. {47} Then one said unto him, Behold, thy mother and thy brethren stand without, desiring to speak with thee."
(Mark 6:3 KJV) "Is not this the carpenter, the son of Mary, the brother of James, and Joses, and of Juda, and Simon? and are not his sisters here with us? And they were offended at him."