Khloe Kardashian appears to have been left a bit shaken by her mother and two of sisters electing to be no-shows at her L.A. birthday celebration last week.

Kardashian celebrated her 31st birthday and held a bowling alley party to mark the anniversary. Kris Jenner, Kim Kardashian or Kendell Jenner all failed to show up for the festivities.

According to RadarOnline, Kim and Kendall's whereabouts are unaccounted for, while Jenner let it be publicly known she was busy vacationing in Paris with her new, much younger boyfriend.

"Khloe stopped being upset by her mom's absence a long time ago," a source told Radar. "Just like Kris did with Rob, instead of actually being there she thought that it was enough to post a birthday message on her social media for Khloe's birthday."

Kris, 59, was busy vacationing in Mexico with her girlfriends when her son celebrated his birthday earlier this year.

She was present and fully accounted for when son-in-law Kanye West celebrated his 38th birthday with an elaborate bash at the Staples Centre earlier this month.

"It says a lot that Kris stopped everything that she was doing to be at Kanye's birthday when Kanye isn't even one of her actual children," the source added.

As for sister Kim Kardashian, the source added, "She was really only bothered by the fact that Kim and Kanye were not at her party because Kim made sure that Khloe was there for Kanye's party."

In recent months, Radar adds Khloe has shown her fans more of her "dark side" as she's publicly struggled with several issues.

Back in May, close friend Chinx Drugz was shot and killed in a drive by shooting in Queens, New York. Days later, five members of her boyfriend French Montana's posse were arrested on the set of a Brooklyn video shoot on drug and weapon charges.

Rapper The Game also recently posted pics to social media of her flashing gang signs and wearing a bandanna commonly associated with the Bloods street gang.