No, he isn’t in the Biblical story. Aaron did not travel with the Magi and was not present at the birth of Jesus. Yet, the way the song is written, he could have been. Originally titled “Carol of the Drum”, the song is about a young boy summoned by the Magi to go with them to present gifts to the newborn King. Upon arriving, the boy realizes he has no gift that is fit to give a king, much less the King of Kings. All he has is his ability to play the drum, so he asks if he can play it for him. As Mary nods permission, he plays his best for the baby Jesus ans is rewarded with a smile from the Lord.
While fiction, the song gives a powerful message. Jesus is the King and is worthy of being honored by us. All that we have to give Him we should surrender to Him. Even our crowns in heaven will be laid back at His feet for He alone is worthy. It isn’t just material things, like gold, frankincense or myrrh, that we can give but also our God-given abilities. All that we give Him should reflect our best effort, like the drummer boy’s song. And a smile from Him, a show of approval, well … that is definitely reward enough. “Well done, good and faithful servant, well done.”
Oh, and in the tv show where the lamb is healed, why not? So watch it with joy, sing along heartily, include it in a cantata. Let the message of giving God our best because He alone is worthy of being praised.