But she was not born with some special grace that nobody else has.How do you know?
The teaching of the complete sinlessness of the Mother of God (1) does not correspond to Sacred Scripture, where there is repeatedly mentioned the sinlessness of [Christ]. But concerning the rest of men it is said, Who is pure of defilement? ... (Job 14:4).
(2) This teaching contradicts also Sacred Tradition, which is contained in numerous Patristic writings, where there is mentioned the exalted sanctity of the Virgin Mary from Her very birth, as well as Her cleansing by the Holy Spirit at Her conception of Christ, but not at Her own conception by Anna. ...
(3) The teaching that the Mother of God was purified before Her birth, so that from Her might be born the Pure Christ, is meaningless; because if the Pure Christ could be born only if the Virgin might be born pure, it would be necessary that Her parents also should be pure of original sin, [and so on back to Adam] ...
(4) The teaching that the Mother of God was preserved from original sin, as likewise the teaching that She was preserved by God's grace from personal sins, makes God unmerciful and unjust; because if God could preserve Mary from sin and purify Her before Her birth, then why does He not purify other men before their birth, but rather leaves them in sin? It follows likewise that God saves men apart from their will, predetermining certain ones before their birth to salvation.
(5) This teaching, which seemingly has the aim of exalting the Mother of God, in reality completely denies all Her virtues. After all, if Mary, even in the womb of Her mother, when She could not even desire anything either good or evil, was preserved by God's grace from every impurity, and then by that grace was preserved from sin even after Her birth, then in what does Her merit consist?http://www.stmaryofegypt.org/library/st_john_maximovich/on_veneration_of_the_theotokos.htm#immaculate_conception
She simply submitted herself wholly, and we do not.I would take it farther and say that we cannot. How come she can and we can't?
Why can't we? We are not controlled by fate. But a newborn is personally blameless like Adam, and aside from living in a corrupted and sinful world (which the Theotokos also lived in), is a blank slate. From a young age however, we allow our temptations to turn into passions, and we refuse to control them. At that point, it becomes a lot harder to return. But it is not impossible, as the multitudes of saints show. And especially some of the holy virgin-martyrs, I would daresay they approach the Theotokos' level of holiness.
The only thing that will always separate us from the Theotokos is that she is the God-bearer. Aside from that, all her virtues, are reachable by anyone who decides to cooperate fully with God from the beginning. Unfortunately most of us don't, and so we spend much of our lives regaining the lost ground of purity, instead of making new progress toward theosis.
All people are born with the ability, with the help of grace, to not sin; not just the Mother of God. But we do sin because we choose to.We are not capable of remaining sinless our entire lives, nor are we born that way. Grace starts at Baptism.
This is where we start getting into Original Sin vs. Ancestral Sin issues.
An infant cannot commit sins. He has no personal guilt for anything, just like the Theotokos. He has inherited a corrupted human nature, yes, but then, so did the Theotokos. If grace begins with baptism, then it doesn't matter, because most children don't manage to commit sins by the time they are baptized anyway.
To say she was less capable of sinning than we are sounds blasphemous to me. She had no free will then. Her virtues are worthless because she was preserved from the battle altogether.Being born without original sin does not mean that she was not capable of falling into sin nor does it mean she did not have free will. Adam and Eve were born in this state and they still fell. The dogma of the Immaculate Conception does not in any way remove the virtuousness of the Mother of God. She could have fallen, but she did not.
Then what was the Immaculate Conception and why was it necessary?