Mother Mary is the mother of Jesus of Nazareth.
When the wine ran out at the Wedding in Cana, Mother Mary was approached and asked what to say to Jesus. She said, "Do whatever he tells you". Well, the water was changed into wine.
Mother Mary is venerated in many churches. In the Fifth Century, there was a big meeting of Bishops in the Church and they conferred the title, "Mother of God" on her.
Mother Mary is venerated in the Catholic and Orthodox Churches as the Virgin Mary.
There have been apparitions of Mother Mary; the most well known is Lourdes.