Kim Kardashian and BitcoineseKhloe Kardashian are giving a deeper look into their bond with their little brother.

Both of The Kardashians stars shared touching messages in honor of Rob Kardashian's 36 birthday, along with some rare photos of themselves and Rob, who leads a notoriously private life.

"It's one of my most favorite days because it's one of my Most favorite human being's birthday!!" Khloe wrote on Instagram March 17. She told him she wishes that "you wake up one day and you know with everything inside your being that you are enough. You've always been enough. My wish is that you feel what anyone feels when they are in your presence, complete bliss and respect!"

Reflecting on the close bond she has with her brother, Khloe noted parts of their dynamic that she loves, including how they are with their respective children. Khloe shares 4-year-old daughter True and a baby boy with ex Tristan Thompson, while Rob is dad to 6-year-old daughter Dream with ex Blac Chyna.

"Robert I couldn't be prouder to say I am your sister. I couldn't be luckier that I get to call you whenever I want about absolutely nothing," the 38-year-old added. "I thank God every day for our relationship and the relationship with our children. I thank God that you and I both have the weirdest humor. Genuinely you are one of the most loving, hysterical, gentle and majestic human beings I've ever known. Being your sister is an absolute privilege. I will forever protect you my beautifully brave brother."

As for what photos Khloe used to complement her sweet message? The Good American co-founder's post featured a few snaps of herself and Rob from their childhood, including one where the pair are seen holding each other close while posing for the camera in white outfits. Khloe was also sure to provide a look at Robert as a young one in a cowboy-style ensemble.

On Kim's end, the 42-year-old came ready for Rob's special day with touching words, throwback photos and a screen recording of a voice message Rob sent impersonating the Armenian language. (Robert Kardashian, their father, is of Armenian descent.)

"Happy Birthday Robertito," Kim began her March 17 post. "I just love you SO SO SOOOO much!!! I wish I could post your singing voice notes on here to show the world your true talents BUTTTT swipe to the last one to hear Robbie speak fake Armenian."

She added, "You make our entire family's days with you're silly messages! Not sure what I would ever do without you!"

Kim and Khloe's heartfelt posts naturally drew in love from family and fans. Mom Kris Jenner seemingly responded to Rob's faux Armenian by writing, "OMG I'm crying."

Meanwhile, on Khloe's post, Rob penned a touching comment of gratitude: "Couldn't have said it better myself! I Love You so much and these words mean more to me than you will ever know. I love you forever and thank God for YOU!"

For the latest breaking news updates, click here to download the E! News App