The siblings joined mum Kris Jenner at the NBC Universal Upfront on Thursday (14 May), where they were supporting their Keeping Up With The Kardashians franchise.
The show airs on E! which is owned by NBC.
Khloe, 30, wore a blue satin frock with a very plunging neckline, while Kylie, 17, went for a more demure high-necked white dress. Check out those matching thigh high splits!
The girls are known to be incredibly close with Kylie recently honouring Khloe on Mother's Day with a heartfelt Instagram post.
She wrote: "Thank you for being you and being another mother figure to me my whole life and doing the same for our nieces and nephews. Whoever one day gets to have you for a mum will be the luckiest in the world. To the ones who've tried and haven't received, I celebrate you on this day too."
The teenager also joked that Khloe shouldn't forget she already has a daughter when she begins her own family.
Meanwhile, the sisters' mum Kris was also at the Upfront looking as glam as always in a crisp, fitted white suit.
All you need to know about Kris Jenner: