Mary was redeemed and saved, but given a singular grace of being saved in ANTICIPATION of Jesus' redemptive sacrifice on the Cross. She was saved from sin BEFOREHAND, in light of His merits.
We've been over and over this, again and again on FR in literally tens of thousands of posts over hundreds of threads. Not blaming you...just making a general comment about the tiresome nature of these threads. You actually asked a good question.
That is fiction. There is nothing in the Bible to substantiate those musings, but there is plenty that speaks against it.