Happy birthday to the Blessed Mother

My coworker and I were talking about her son's birthday, which is today, September 8. I said that it is also my grandmother's 85 birthday (I called and left the birthday song on her voicemail). I then said that it is the Blessed Mother's birthday. My coworker asked me how I knew. I told her I had remembered for a while. I guess I learned it in college in bible study, and realized it was the same day at my grandmother, and since then was always able to remember their birthday.

My coworker and I then discussed the Solemnity of the Immaculate Conception, celebrated on December 8. My coworker thought that the Immaculate Conception referred to when Mary conceived Jesus. I said no, this was her conception we celebrate because we perceive her soul to have been conceived without sin. My coworker is not Catholic, and had never heard that Mary was without sin. I knew I had been taught that, so I had to do some internet research. There is nothing specific in the Bible stating such, but there are several areas that construe she was without sin:
http://www.americancatholic.org/features/saints/saint.aspx?id=1223
"In Luke 1:28 the angel Gabriel, speaking on God’s behalf, addresses Mary as “full of grace” (or “highly favored”). In that context this phrase means that Mary is receiving all the special divine help necessary for the task ahead. However, the Church grows in understanding with the help of the Holy Spirit. The Spirit led the Church, especially non-theologians, to the insight that Mary had to be the most perfect work of God next to the Incarnation. Or rather, Mary’s intimate association with the Incarnation called for the special involvement of God in Mary’s whole life. The logic of piety helped God’s people to believe that Mary was full of grace and free of sin from the first moment of her existence. Moreover, this great privilege of Mary is the highlight of all that God has done in Jesus. Rightly understood, the incomparable holiness of Mary shows forth the incomparable goodness of God."

We celebrate the Conception on December 8, which nine months later would be September 8, today, which we celebrate as her birthday!
http://www.ewtn.com/library/MARY/MARYBRTH.HTM
"The present Feast forms a link between the New and the Old Testament. It shows that Truth succeeds symbols and figures and that the New Covenant replaces the Old. Hence, all creation sings with joy, exults, and participates in the joy of this day.... This is, in fact, the day on which the Creator of the world constructed His temple; today is the day on which by a stupendous project a creature becomes the preferred dwelling of the Creator" (Saint Andrew of Crete).
"Let us celebrate with joy the birth of the Virgin Mary, of whom was born the Sun of Justice.... Her birth constitutes the hope and the light of salvation for the whole world.... Her image is light for the whole Christian people" (From the Liturgy).
As these texts so clearly indicate, an atmosphere of joy and light pervades the Birth of the Virgin Mary."

So today is a very special day. Today we celebrate the birth of the Mother of Christ.