The thread eagerly awaits their names, and your evidence. I really hope that your evidence doesn't rely on a simplistic English translation of adelphos.
From the Bible that Catholics claim their church wrote, and used the Greek word for *brothers* instead of the Greek word for *relative*.
Matthew 13:55 “Is not this the carpenter’s son? Is not His mother called Mary, and His brothers James and Joseph and Simon and Judas?”
Mark 6:2-3 And when the Sabbath had come, He began to teach in the synagogue; and the many listeners were astonished, saying, “Where did this man get these things, and what is this wisdom given to Him, and such miracles as these performed by His hands?”... “Is not this the carpenter, the son of Mary, and brother of James, and Joses, and Judas, and Simon? Are not His sisters here with us?”
Why is it so important that Mary be perpetually virgin?
How does that affect our salvation?
How does that affect our relationship with God in Christ?
Does it affect the atonement and the work of redemption that Jesus worked on the cross?
Why is it so important that Mary be perpetually virgin?
I offer this as a possible explanation. Maybe the early Christians felt it was necessary for Mary to remain a virgin to fulfill the following prophecy from Ezekiel 44:2
This gate shall be shut, it shall not be opened, and no man shall enter in by it; because the Lord, the God of Israel, hath entered in by it, therefore it shall be shut.
John Gill wrote:
“Some of the ancients interpreted it of the Virgin Mary, by whom Christ came into this world in human nature, being born of her, a virgin, who had never known man, and as is thought never did after the birth of Christ; nor were any afterwards born of her; no man might come into the world by her, by that self-same way the incarnate God did, and for that reason. This sense is approved of, not only by Papists, but by many Protestant writers.”
https://www.studylight.org/commentaries/geb/view.cgi?bk=25&ch=44#2