Khloe Kardashian and Kylie Jenner Credit: Courtesy of Khloe Kardashian

Tears of joy! Khloe Kardashian and Kylie Jenner couldn't help but breakdown during Kanye West's epic proposal to big sister Kim Kardashian on Monday, Oct. 21. The two sisters -- alongside several family members and close friends -- witnessed the Yeezus rapper get down on bended knee to ask Kardashian's hand in marriage at the AT&T Park in San Francisco, Calif. 

"Clearly @kyliejenner and I were having a moment!" the 29-year-old reality star wrote about Kim and Kanye's special night on Wednesday, Oct. 23. "#TearsOfJoy #Sisters." Alongside the caption, Kardashian shared a sweet photo of herself and Jenner, 16, crying moments after West, 36, popped the big question.

"Wow!!!!! Am I dreaming??!?!" Khloe previously wrote via Twitter. "Tears of JOY!!!!!!! Wow!!!!!!"

The "All of the Lights" singer shocked the sisters and many others when he organized an over-the-top surprise proposal for Kardashian on her 33rd birthday. In a new video, West can be seen proposing to the mother of his daughter North in pitch darkness as an orchestra plays classical music. As Kardashian kissed and embraced her future husband, family and friends then emerged from dugouts to congratulate the couple.

The very next day, the blushing-bride-to-be wrote her own reaction via Twitter. "YES!!!" she wrote on Oct. 22, as she shared a photo of her massive (and stunning!) Lorraine Schwartz diamond rock.