The socialite revealed that she has loved seeing her younger sibling's transformation throughout the competition in a new interview with Celebuzz.
"Rob is so excited to have made it this far and I am so proud of him. Doing this show has really changed Rob. He's really grown up so much and it's been incredible to watch him each week," she explained.
Kim went on to say that the entire family was thrilled to see Rob and professional partner Cheryl Burke earn their first perfect score of the season during the first part of the Dancing with the Stars finale on Monday night.
"We were all so blown away by Rob's performances last night. His freestyle dance was my favourite of the whole season!! Each week he works so hard and is always prepared, but never knew he would get a perfect score!! We were all amazed and so happy!" she said.
Sister Khloe Kardashian added: "Watching Rob improve week after week has been so special for my entire family. His dedication is truly beautiful. We're all just so proud of him!"
Rob has confessed that earning a perfect score was the best way to end the season on Dancing with the Stars.
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