"People think you weren't there," Khloé said to Kylie in a previous Snapchat video about Kris Jenner's party as the younger sister replied: "I was"


Pregnant Khloé Kardashian shared photo proof that sister and fellow mom-to-be Kylie Jenner was indeed at their momager Kris Jenner‘s annual Christmas Eve party.

On Tuesday, two days after the bash, Khloé, who confirmed that she and NBA boyfriend Tristan Thompson are expecting their first child together, shared photo booth shots of her and Kylie, who covered up in a leather jacket.

Sources told PEOPLE back in September that Khloé, who is nearly six months pregnant, and Kylie are due around the same time.

While Khloé, 33, and siblings Kourtney Kardashian, Kim Kardashian West and Kendall Jenner posted plenty of memories from the Christmas Eve party with fans and followers, Kylie — who is expecting her first child, a baby girl, with rapper boyfriend Travis Scottdid not appear in any photos from the bash shared to social media. But a source told PEOPLE she was there celebrating away from the cameras.

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Khloe KardashianKylie Jenner/Snapchat
Credit: Kylie Jenner/Snapchat
Khloe KardashianKylie Jenner/Snapchat
Credit: Kylie Jenner/Snapchat

Kylie looked great but didn’t really draw any attention to her baby bump,” the source said. “She still acts like she wants to keep her pregnancy private.”

Adding, “Everyone had the most amazing time. Kris always throws the best parties. It was all gorgeous. There was no drama.”

Credit: Khloe Kardashian/Instagram

On Christmas morning, all the family members, including brother Rob Kardashian, gathered at Kourtney’s house to open presents and celebrate the holiday in matching elf-patterned onesies and beanies.

“Merry Christmas! People think you weren’t there last night,” Khloé said to Kylie in one Snapchat video as the younger sister replied: “I was.”

“She’s a secret little bunny,” Khloé teased.

WATCH: Khloe Kardashian Confirms Pregnancy with Boyfriend Tristan Thompson: ‘My Greatest Dream Realized’

Before the Christmas weekend, Kylie and Khloé previously co-starred in a Kylie Cosmetics YouTube video together, during which they discussed their Lip Kit partnership called In Love with the Koko Kollection.

“We created them. It’s our baby together, we have eight!” Kardashian proudly told Jenner, who responded: “We have so many babies, who knew?”

The sisters are all currently expecting — Kim will welcome her third child, a daughter, via surrogate — and an insider previously told PEOPLE they’re all prepping for their new additions.

“Khloé and Kylie are both starting to plan out their nurseries, and Kim and Kourtney are also involved in the process,” said the insider. “All the sisters are super excited, and Kris has been helping as well.”