Mary received from Jesus "the mission of making the Church one family"

Christ Jesus gave his life "to bring together in unity the scattered children of God" (John 11:52). Mary, his mother, also has an important role to play in this plan for unity:

"The Mother's presence is a guarantee of fraternity and of welcoming the Holy Spirit. Only Mary could make the apostles of Jesus, before and after Pentecost, one heart and one soul (cf. Acts 1:14 and 4:32). It is as if Christ wanted to show us that he has entrusted to his Mother's maternal care the mission of making the Church a single family where love reigns, and where we love above all those who suffer most. Yes, in Mary we have the model of a love without frontiers, the bond of communion between all of us who are, through faith and baptism, disciples and brothers of Jesus." 

(John Paul II, Mass at the Shrine of Our Lady of Suyapa in Tegucigalpa, Honduras. Homily, March 8, 1983).

Source: Marian Encyclopedia