The "Twelve Days of Christmas" refer to the eight days of the Christmas Octave from December 25 to New Years Day, and the four additional days up to and including the eve of January 6, the traditional date of the Epiphany. In the USA and many other countries, Epiphany is now celebrated on the first Sunday after New Years, so the exact number 12 does not necessarily apply. But the point is, don't throw out the tree on the 26th--the birth of the Savior can't be celebrated adequately in one day. Let the celebration continue through at least through the Feast of the Epiphany--if not through the Feast of the Baptism of the Lord.
According to the Handbook of Catholic Sacramentals by Ann Ball, the famous song about the 12 Days of Christmas was written in England as a catechism song for young Catholics in the days when it was illegal to practice or teach the Catholic Faith. It contains hidden meanings intended to help children remember lessons of faith. Instead of referring to an earthly suitor, the “true love” mentioned in the song really refers to God. The “me” who receives the presents is symbolic of every baptized person.
There appears to be no conclusive historical evidence to prove this origin of the song, Nevertheless, the traditional association between the gifts mentioned in the song and various spiritual gifts is a fun way to turn a seemingly secular Christmas carol into a valuable catechetical tool. So let's have fun with it!
Partridge in a pear tree Jesus Christ, symbolized as a mother partridge that feigns injury to decoy predators from helpless nestlings.
Two turtle doves Old & New Testaments
Three French Hens Faith, hope, charity
Four Calling birds The Four Gospels
Five Golden Rings The Pentateuch or Five Books of Moses (Genesis through Deuteronomy)
Six geese a laying Six days of creation
Seven Swans a swimming 7 Gifts of the Holy Spirit
Eight maids a-milking 8 Beatitudes
Nine Ladies Dancing Nine Fruits of the Holy Spirit
Ten Lords a-leaping 10 Commandments
Eleven pipers piping The 11 faithful disciples
12 drummers drumming 12 articles of the Apostles Creed