Appearances in Christmas specials
The Christmas specials Bamm-Bamm has appeared in have featured him and Pebbles at various ages, ranging from toddlers to preteens to married parents with their own children. However, Bamm-Bamm's role in the series' original Christmas episode, "Christmas Flintstone", is rather minor. He is seen playing with his adoptive father and their pet Hopparoo, Hoppy, early on in the episode, while Barney tells Betty about Fred getting a part-time job at Macyrock's Department Store. However, he is not seen again in the episode until the closing scene with the two families celebrating Christmas together.
Chronologically, Bamm-Bamm's next appearance in a Christmas production is the series' fourth Christmas special, A Flintstones' Christmas Carol, which appears to take place shortly after the original series (possibly a year after the events of "Christmas Flintstone"). Here, Bamm-Bamm is now able to say words other than his own name, and he has the part of Tiny Tim in the Bedrock Players' stage production of A Christmas Carol. He ends up getting stage fright when he is supposed to say "God bless us, everyone!" at the very end of the show, so Pebbles ends up saying the line instead.
The second Flintstones Christmas special to be produced, A Flintstone Christmas, chronologically takes place when Bamm-Bamm and Pebbles are at elementary school age. At the very beginning, Bamm-Bamm and his adoptive mother are shown helping Wilma and Pebbles bring their Christmas tree home. Later, after Fred places a heavy ornament in the wrong spot on the tree and causes it to fall over, Bamm-Bamm lifts the tree up and places it back in its upright position. He and Pebbles are later seen at the Ladies' Auxiliary's party with the other children, becoming impatient in waiting for Santa (Fred) to show up. At the very end of the special, he and Pebbles, along with their respective fathers, are shown waving to Santa when they see him flying in the sky.
Finally, in A Flintstone Family Christmas, the only Flintstones Christmas production that takes place after I Yabba-Dabba Do! and Hollyrock-a-Bye Baby, the adult Pebbles and Bamm-Bamm call to say that they and their kids, Chip and Roxy, are flying from Hollyrock to spend Christmas with their families in Bedrock. Midway through the special, however, their flight is delayed by bad weather. Fortunately, by the end of the special, the couple and their children eventually arrive at the Flintstone residence in time to celebrate Christmas with their families, including Pebbles' new adopted brother, Stoney. Though he was voiced by Jerry Houser in the aforementioned made-for-TV movies, Bamm-Bamm oddly does not have an actual speaking part in this special, outside of singing Christmas carols at the end.
Outside of The Flintstones itself, Bamm-Bamm also starred in "Cave Kid Christmas", the Christmas episode of his and Pebbles' short-lived spin-off, Cave Kids. As the series takes place when the two are preschoolers, this would indicate that "Cave Kid Christmas" comes between A Flintstones' Christmas Carol and A Flintstone Christmas in chronological order.