"Amen!" at least twice. The way is the Word, not the Greater Catechism, or some other uninspired, errant document. But history can sometimes solidly refute speculation, particularly Augustus' bronze tablets for all to see across the known world and across time, irrefutable.
Mary's genealogy is given specifically, though not explicitly stated, where Joseph was not the father in the flesh, her descent from David through Nathan (tribe of Jdah/scepter) cannot be questioned.
But my position here is that Jesus' flesh had no component of her flesh -- that she was a faithful, holy host with a Christ-like yielding of her body ("Lo, I come to do Thy Will, O God!"), accepting a perfect seed implanted by The Holy Ghost -- just as a virgin today could become the host of another couples' seed -- and trusting The God to vindicate her submission against any assertion of illegitimacy.