For Catholics Tradition (big “T”) is as important as Scripture. Before we had Scripture (at least New Testament Scripture) we had Tradition. Not everything that was written in the early Church was incorporated into the New Testament. Not everything that was left out was false or even bad, it was simply not inspired. Christians have always known things about Mary that were not recorded in Scripture.
One of these writings, The Protoevangelium of James, is thought to have been written as early as 150 AD. This document was specifically mention by Origen, the late second century theologian. He did not considered it to have actually been written by James. This is the James who according to the manuscript was the son of Saint Joseph by a prior marriage, and the brother of Jesus mentioned in the Gospels, often called James the Just. James was a leader in the early Church in Jerusalem. It was often common at the time for authors to attribute their works to well known saints or religious leaders.
This document contains much of what is now generally accepted about Mary's history which is not recorded in the Gospels. It names her parents Anna and Heli, who is also known as Joachim. He was of the royal family of David. Anna was said to have been of the priestly family of Aaron, so in Jesus was combined the bloodline of both the royal and priestly families.
Mary is also said to have been presented at the Temple. Under Jewish law it was required, under the covenant, that first born males be presented to the Temple to be consecrated to God. And so Jesus was, in what we called the Presentation. Sometimes other very special children were also presented at the Temple to be consecrated to God. So it was said of Mary. Tradition (little “t”) says that Mary was 3 years old at this time and took a vow of virginity.
Tradition also tells us that St. John the Evangelist eventually settled in Ephesus, in Greece. As previously mentioned this was where the Council of Ephesus was held and the synodal letter of that council reads:
Wherefore also Nestorius, the instigator of the impious heresy, when he had come to the city of the Ephesians, where John the Theologian and the Virgin Mother of God St. Mary estranged himself of his own accord...There are several places in the Eastern world which lay claim to spot where the Blessed Virgin left this mortal pale. No one claims to have her body, nor have they ever. Catholics, from the days of Early Christianity, have venerated and honored the relics of the Saints. The location of the graves of St. Peter and St. Paul are known to us, as is the resting place of St. Steven the first martyr mention in Scripture. Christians have never claimed to have relics of the Blessed Virgin. One of the earliest feasts celebrated by the Church declares that Mary was assumed directly into heaven. In 602 AD this feast was formalized for the Universal Church as the “Falling asleep of the mother of God” as it is still known today in the Eastern Churches. While this has been a belief of the Church from early times Pope Pius XII in 1950 proclaimed it a dogma and created it as a major feast. It is also celebrated in the Eastern Churches on the same date of August 15.