In various places in Grandma's house is a picture of Cartman, one of the shepherds, from Mr. Hankey, The Christmas Poo.
Over the meadow… - should be "over the river…"
When the family and friends are seated at table, Kenny sits between Kyle and Great-Grandma. But when Kyle holds Great-Grandma's catheter bag, Kenny is no longer between them. He's back between them when the camera shows the whole table again.
Stan didn't bring a sleeping bag with him when he snuck out to Cartman's place. How did he get it, then?
Blooper: When Uncle Howard is first introduced via TV, the TV screen is clean. When he retorts that he doesn't look good, the smear of chocolate Elvin's fudgecicle is to leave on the TV is already there. Soon after, Elvin throws his fudgecicle at a clean screen, and the smear reappears.
Long shots of the dining scenes show Cartman wearing his coat over his new shirt. Closeups show him with his coat off.
Cartman goes to sleep with his cap on, but wakes with it off. He puts it back on just before he goes upstairs. Urkel's picture is not on his sleeping bag anymore.

Uncle Howard's prison number: 29081.
Charlie Mansons's prison number: 06660.
When Howard and Manson break into Grandma's basement the TV has three cracks on the screen glass, and this is the case until Manson turns on the TV the next day. The cracks are gone while Manson watches (a spoof of) It's a Wonderful Life.
The last two acts of It's a Wonderful Life are reversed in the spoof Manson is watching. Bailey's walk through Main Street should precede his realizing that Mary is real.
Good idea. Have access to your children's friends' relatives' numbers. Sharon has Cartman's Grandma's number and address in Nebraska.
The theater's name in It's a Wonderful Life is the Bijou, just like South Park's theater.
Mall Hankey looks and sounds like Dian Bachar.
One of the mall stores is "Deified Stakeboards." The other is "Corn Husker Cafe"
The orange Smoothie is first mentioned in The Spirit of Christmas: Jesus Vs. Santa, where Jesus offers one to Santa at South Park Mall. Many malls have an Orange Julius in them. Where better to get an orange Smoothie?
The high-speed chase looks like O. J. Simpson's in 1994.
This is Robert Pooner… - Robert Pooner is a Channel 4 news reporter in Nebraska. But that's not all. The second Spirit of Christmas is a Robert T. Pooner presentation, and the COPS segment in Chickenfucker was produced by Robert T. Pooner.
Palmoral (pretty clever!) = Armor All
"Thoughts & Reflections" is written by Chales W. Manson. Manson's real name is Charles Milles.
When Manson walks past the bookshelf in the cell "OBSERVATIONS FROM THE FOREST" is much smaller than "Are You There God? It's Me. Manson," but when he goes to bed, "OBSERVATIONS FROM THE FOREST" is bigger than "Are You There God? It's Me. Manson."
"Are You There God? It's Me. Manson" = "Are You There God? It's Me. Margaret"
Mr. Hankey has come a long way. In Mr. Hankey - The Christmas Poo only Kyle and Chef know of him, until first Wendy, then Stan, then others came to believe:
"Wait, I thought Mr. Hankey only came at Christmastime." - Cartman, Chef's Salty Chocolate Balls
Kyle has to find a way to get Mr. Hankey to the surface so he can fight the South Park Film Festival. A quick film called "Me and Mr. Hankey" is made, and Mr. Hankey chases every film festival guest out of South Park.
"Dude, I thought Mr. Hankey lived in the sewer." - Stan, Merry Christmas, Charlie Manson!
Mr. Hankey has made his first actual film: "The Grinchy-poo Who Stole Christmas." and has taken Santa's place as Christmas icon in some places - mall Hankeys appear evrywhere.