Kylie Jenner forgot to inform her sisters about her 18th birthday bash this past August. In a sneak peek of Keeping Up With the Kardashians, Khloe Kardashian has some choice words for her half sister.

"What a little bitch Kylie is," Khloe tells Kourtney Kardashian. "I'm calling her now."

When the birthday girl gets on the phone, Khloe tells her, “So I just heard you're throwing a huge birthday bash … and Kourtney and I haven’t been invited yet. Is there a reason why?” The now-18-year-old explains that she still needed to secure a location before she invited anyone.

“Well, don’t you want us to hold the date?” Khloe asks. “You’re never going to be busy on my birthday,” a sassy Jenner informs them.

As previously reported, the makeup maven ended up celebrating her 18th birthday at Bootsy Bellows in West Hollywood on Aug. 10, where she was gifted a white Ferrari from boyfriend Tyga.

Watch the sister moment above. Keeping Up With the Kardashians airs Sundays at 9 p.m. ET on E!

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