[marajade]

I read Mark 3, did you? Mark 3 clearly states that Jesus is asked about his physical brother and mother and Jesus responds what about them.

I believe the Church is built upon Jesus Christ. Emphasis Jesus Christ.

[wagglebee]

There is no mention to physical brothers or sisters in Mark 3. There is mention of physical relation to the Blessed Mother, hence the title Mother of God.

I believe the Church is built upon Jesus Christ.

No, Jesus said "on this Rock (Peter) I will build My Church." He did not say to Peter, "build My Church on Me."