A cycle C reading for Holy Family, in part, covers the whole meaning for me:
See what love the Father has bestowed on us that we may be called the children of God. (1 John 3:1)
Jesus, in taking on flesh, has become a brother to all, and so we are grafted by adoption into his holy family. And so, blessed Christmas to all my siblings out there. Every one.
Image credit of the Christmas Tree Nebula: By NASA – NASA/JPL-Caltech/P.S. Teixeira (Center for Astrophysics) – en:Image:NGC 2264Downloaded from: http://www.nasa.gov/multimedia/imagegallery/image_feature_476.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4207810