Totally illogical...Mary couldn't have been born 'immaculate' with parents who were soiled with sin...
Both of Mary's parents would have to have been sinless as well...
The term concpetion is misleading. The dogma properly relates not to her physical conception but to her “ensoulment,” when she becomes a person. The two actions are separate.
No more than Jesus could have been born of a virgin.
In both cases, the intervention of the Holy Spirit was necessary. There is some confusion on this thread that it was absolutely necessary for Jesus to:
a) be born of a woman unstained with Original Sin, or
b) to be born of a virgin, or
c) to be born of a woman at all (instead of just being formed out of the dust like Adam)
God chose all of the above because it:
a) effectively reverses the sin of Eve
b) fulfills the prophecies of Genesis and Isaiah, and
c) demonstrates that the family unit (Father, Mother, and offspring) reflects the love of the Holy Trinity.
Where Eve was tempted by the serpent and obeyed, Mary was solicited by the angel and obeyed. Where the stain of Original Sin is the result of Eve's folly, Mary's role would be a demonstration that God has the power to purify our souls. Where Adam and Eve sought to have dominion over God, Mary declared herself the "handmaiden" of the Lord - essentially, His slave.
These are not coincidences. This is what God planned. And we celebrate this as part of our faith. If you don't wish to celebrate with us, that's up to you. But as much as you may try to pin us as "focused" on Mary, it's only because you don't recognize that the center of our Church, the Holy Eucharist, is the body and blood of Christ.