The Brown Scapular isn’t something that Our Lady just came up with out of the blue. It has biblical symbolism that goes back to the Old Testament.
I can imagine that Mary, with her motherly heart and closeness to her Son, was ever-so proud of the Apostles. I can imagine her face, beaming with joy, and her lips offering prayers of praise and thanksgiving to God. Because of the important position the Apostles had in Jesus’ life, they must have had an important position in Mary’s life as well.