Interesting.
Thank you.
This tells us that, according to Tradition, Mary died a natural death. But it does not close the loop for me and answer why (or if) she HAD to.
Immaculately conceived and living a stainless life, she would seem to not have been under the curse of Adam, and therefore to be immortal like Adam and Eve were before the Fall.
I guess the answer really must be that, if she died, it was because she chose to "fall asleep in the Lord" and go to her Son. I would presume that Tradition would somewhere say that.
I could honestly talk on this subject for days - but the short of it is - Our Lady died, not because of the punishment due us all for sin - for in Her was no sin, rather out of Her great humility. Her humility would not allow Her to be assumend, body and soul into Heaven without first submitting to the same death Her beloved Son did, but also proving that by so doing, She, as our Heavenly Mother, submitted to that same death that befalls us, Her children.
Mary's Assumption would have been impossible without Jesus' Resurrection, for it is His resurrection power which will glorify our bodies (Philippians 3:21). This dogma depends upon and reaffirms the Resurrection of Jesus Christ.