Point me to the line.
There is nothing in "THE GOSPEL" that precludes Mary from having further children. In fact, they are mentioned several times in the gospel texts. "DOCTRINE" is a whole different issue, but if you want to go by exactly what the Bible says, rather than later interpretations, the answer is clear.
None of this doctrine of the perpetual virginity is ever mentioned in the Gospel or in any of the other books of the Bible. They are later day inventions.
Are we to understand that someone like you accepts only what is written in the the Gospels, and rejects the rest of the New Testament?
Jesus’ brothers are mentioned; Mary’s children are not.
If we’re going to read “as written.”