The clip has sent fans who hadn't connected the dots to the star's former movie role wild, prompting a flurry of tweets and posts from mind-blown Schitt's Creek fanatics.
The Schitt's Creek Instagram account itself even reposted some of the tweets as a reminder of her time as the McCallister matriarch.
"It's that time of year again", the post was captioned.
The series of tweets featured such gems as: "Schitt's creek fans: I just about schitt my creek when I found out the actress who played Moira Rose also played the mum in Home Alone."
As another Catherine O'Hara fan pointed out in the comments, she was also the voice of Sally in Tim Burton's The Nightmare Before Christmas.
O'Hara isn't the only Home Alone alum who has provided a welcome throwback to the Christmas franchise in recent months.
Viral social media sensation Macaulay Culkin shared a selfie in October wearing a face mask featuring the open-mouthed screaming expression made famous in the 1990 film original film.
"Just staying Covid-safe wearing by the flayed skin of my younger self. Don't forget to wear your masks, kids," the star, now 40, wrote.
Within an hour of his posting, the tweet topped 111,000 likes and more than 17,500 retweets.
