Your Church's teaching, nor Scripture's.
On the contrary, Scripture teaches taht ALL have sinned and fall short of the glory of God.
All is all, not most, not some, not everyone but one. All.
If Mary did not inherit her sin nature from her father, she was not human, therefore Christ did not share in our humanity.
the "assumption" which states that Mary was bodily assumed into Heaven by the power of God. (didn't ascend on her own)
There is no Scriptural support for hat either and just because Scripture doesn't come out and say something didn't happen does not give license to anyone to make stuff up and pass it off as truth when its not.
The ‘popular’ opinion is that Joseph died somewhere before Jesus started His ministry.
Therefore, Mary would have been a widow.
It appears to be that she had no BROTHERS-IN-LAW to give her ‘offspring’ like ONAN was supposed to do.
Or; she DID already have other children.
What say ye?