This is the claim: That Vatican II has the most complete treatment of Our Lady of any Ecumenical Council! And, this is just what Dr. Miravalle shows so well.
Check out a summary of his videos from airmaria.com.
“Dr. Miravalle explains that the Second Vatican Council’s doctrine on Mary is possibly the most complete treatment of Our Lady in any Ecumenical Council since the origins of the Church. In this video and the following two, he intends to show where the Council points to for authentic Marian doctrinal development“
You can check out the videos from airmaria.com Linked Here. I highly recommend this series of videos. They are great in explaining Vatican II’s Marian content.