Kaley Cuoco Reveals Her Sister On Instagram

06/30/2017 04:46 pm EDT

Kaley Cuoco celebrated "National Sibling Day" by giving a special shout out to her sister on Instagram. The Big Bang Theory star shared an all-new selfie on social media that showed the two of them putting their strikingly good looks on full display while spending some quality time together

The 31-year-old actress captioned the snap: "#nationalsiblingday goes out to my sidderrrr!! @bricuoco."

The image shows Kaley on the left with her signature blond locks flowing down her sides. Her sister, 28-year-old Briana Cuoco, was on the right and was sporting a patterned dress with a high neckline. The siblings look quite similar and some fans event went as far as to say that Briana looks like exactly like Kaley but with a darker hair color.

Kaley Cuoco and her sister are a tightly-knit duo that regularly shows their support for one another. The Wedding Ringer star has asked Briana to be her date to multiple red carpet events and even helped her sis snag a small role on The Big Bang Theory.

Last year Briana Cuoco starred in a show called Lizzie the Musical. At the time, she revealed some of the most important advice that Kaley has ever given to her.

Briana said the words of wisdom that Kaley has always shared with her are: "Don't be a jerk. Keep your feet on the ground. Work hard, and don't take yourself too seriously."

In the past, Briana regularly made a point of clapping back at Kaley's haters on social media.

"People can be especially mean on Instagram," Briana said. "I shut them down! My sister fangs come out. She actually texts me and says, 'Sis, thanks for having my back.'"

When Kaley Cuoco isn't taking a moment to show her appreciation for her younger sister, she has frequently been spending time with her boyfriend Karl Cook. On Sunday, Kaley and her beau spent an afternoon enjoying a movie date and she took to Instagram to commemorate the moment with an adorable snap.

Cuoco captioned the pic: "Going to a theatre that serves wine while watching my favourite childhood movie (Beauty and the Beast) serves up quite the combination. I cried the entire time. It was magical! I knew every word to Be Our Guest. In other news, this guy stole my shirt. In even more news, we saw this movie at 3:30 in the afternoon #dateday @mrtankcook."

To keep up with Kaley Cuoco, be sure to follow her on Instagram here.

Were you surprised to see what Kaley Cuoco's sister looks like?

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[H/T Instagram: Kaley Cuoco, Entertainment Tonight]

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