Kim Kardashian wasn't invited to sister Kendall Jenner's birthday party

Kendall Jenner took a break from her whirlwind year and celebrated her 19th birthday with a few close friends Tuesday.

"We're going to go to a family lunch, and then later tonight Kendall's having like 15 people over for a little girls' party," big sister Khloe Kardashian told People Monday. "I don't know if it's even a party, but a girls' gathering."

One girl who wasn't invited? Sister Kim Kardashian.

"I asked Kim, 'Oh, are you going tonight?' and she was like, 'I didn't know Kendall was doing anything!'" Khloe revealed. "I don't know if she was late to be invited, but I'm invited, so I feel good about that!"

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