That's excellent! I often wondered why +Luke elaborated so on the Blessed Mother, and not +John whose charge she was left in.
In Jesus' life there were mysteries, Luke's part was to explain the history of the glorious mystery of His birth in full detail. John's part seems to have been to intellectually convey the mystery of salvation more fully on an almost philosophical level. One recaps the past, one frames the future. This is my ignorant view. V's wife.