Why does Mother Mary pray for us?

Let me begin with a disclaimer, as this is going to sound like I am denying a central tenet of the faith. I'm not, and indeed this is not all that critical an issue to determine whether we are to be saved. And yet, let me say, I love Mother Mary, and I pray the Rosary frequently. I have even written an expanded set of daily mysteries that I call the Wildflower Rosary, to make it more useful for teaching about Jesus. I think it would be edifying for Protestants also to pray the Rosary, even if they feel they would need to alter it somewhat. They can say decades of the "Jesus prayer" that Orthodox Christians say, in place of the "Hail Mary," if they want. But here, I begin my rant.

The Catholic Church has gone too far in its teaching about Mary. This is a case where the "traditions of men" have grown into accretions on the faith. We need to discern, instead, the earliest teachings of the Church, and fortunately, those are clear. Yes, she is certainly the Mother of God and the Queen of Heaven, whom we love as the Mother of the Church. That much can be supported from the Scriptures. Thus, we can reverence her, and speak to her in prayer, but we must not worship her. She is only human, like us. She can indeed pray to God, in the person of her Son, on our behalf, but that is the same intercessory prayer that we can do for others. 

The Early Church Fathers have always taught that we can pray to Mary and the Saints. In the creeds, we call it the "Communion of Saints," and that's why we keep track of canonized saints, to know whose prayers are most effective. The Saints can hear us, and like the Angels, they observe the living and see how we behave here on Earth. They can pray for us, but they do not act as mediators for us. Mother Mary, too, can pray for us, and her prayers are often quite effective, but she is not the royally authorized "Mediatrix" pleading our case to Jesus that the Catholic Church has lately promoted her to be.

Only Jesus Christ, the Son of the Living God, can stand as our Mediator before the Father. It is sure and certain what He said: "I am the Way and the Truth and the Life. No one comes to the Father except by Me." 

There is only one person who can act as Mediator between you and God the Father, and that is Jesus, the uniquely divine and human Son of God. He is the one who paid the penalty for our sins on the cross, and He died so that we might live. Only Jesus will stand beside us on the Day of Judgment, and He can declare that we are covered by his blood and our sins are forgiven. Jesus knows the quality of our faith, and whether we love Him. He does not need anyone to stand for us, to speak for us. We stand before Him all by ourselves, and He will either commend or deny the way we have lived our faith for Him. 

But Jesus can also hear how many voices speak to ask Him to grant us mercy, just as we have prayed for others. He hears his Mother asking Him to overlook our sins and see only our faith, to be generous with his mercy. It's just like the day He heard her ask Him to do something when the wedding at Cana ran out of wine. There is no sense of compulsion, but how can He refuse his beloved Mother? And has she not asked us to "do whatever He tells you"? Of course, Mary will pray for us because we are also her children. It's her natural response to our request. That is not mediation. It's petition and supplication, and it's what we too are supposed to do for those who need our prayers.