Khloé Kardashian won't be keeping up with one family tradition this year.

The Kardashians star revealed that she and kids True Thompson, 6, and Tatum Thompson, 2—who she shares with ex Tristan Thompson—would have to miss their annual family Christmas Eve get-together this year. But they do have a very good reason.

"Tatum was sick the entire weekend," Khloé wrote on her Instagram Stories Dec. 24, "and now my TuTu is sick. For the first time in a long long time we will miss Christmas Eve."

The 40-year-old added, "I feel so terrible for my sick littles. No fun but I pray we are fine for Santa tomorrow!!!"

Still, Khloé was trying to keep spirits bright at home, sharing that she and her kids were watching 1964's classic stop motion cartoon Rudolph the Red-Nosed Reindeer.

And luckily for the Good American founder, she and her family have been in the holiday mood for a few weeks now, as Khloé gave a peek at pre-celebrations with True, Tatum and brother Rob Kardashian's 8-year-old daughter Dream Kardashian.

In a slew of videos shared to her Instagram Story Dec. 17, the reality star showed off True's holiday dance routine, which she performed with an assist from Dream and Tatum in front of the family's giant Christmas tree. Khloé could be heard cheering on the trio from behind the camera as they spun around each other.

Although she and her kids won't get to spend Christmas Eve with the fam, they will still have plenty of presents to look forward to as mom Kris Jenner shared she's been busy planning gifts for months.

"We have this family chat going around," Kris recently told E! News, adding that the grandkids will text her what's on their holiday wish list. "It's really fun. Some of the things that they ask for are really cute."

Kris also noted how the lists have changed over the years as her grandchildren keep getting older.

"They're growing up," the 69-year-old added. "They're loving new things. One year, they'll be into a certain type of doll. And then, you clearly see that shift when it's the following Christmas."

For a look at how the Kardashian-Jenners have already begun to celebrate the holiday season, keep reading.

Kylie Jenner's daughter Stormi Webster, 6, got hands-on as she helped decorate the Christmas tree.

Kylie gave her followers a closer look at her ornaments, which included popcorn, snowmen and mini Santas.

With the lights strung and the decorations hung, Stormi cracked a smile in front of the completed tree.

And Stormi chose to make her own personal Christmas tree a bubble gum pink shade. 

Kylie's son Aire Webster decked out his own tree with motorcycle and train ornaments.  

Kourtney Kardashian's vibe right now is just living life—in the comfort of festive PJs and Santa-themed slippers.

One way Kourtney really made her Christmas decor stand out? An inverted tree, of course.

Kourtney also leaned into the seasonal color with a monochromatic theme.

What's better than one Christmas tree? Judging by Kourtney's foyer, a minimum of four.

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