He’s back! Rob Kardashian made a rare appearance on Wednesday’s episode of Keeping Up With the Kardashians for sister Kim Kardashian‘s 40th birthday.

The Skims founder turned the big 4-0 on October 21, and the family got together to plan an amazing surprise. Kim’s mom, Kris Jenner, and sisters Kourtney Kardashian and Khloé Kardashian enlisted the help of the family’s longtime party planner, Mindy Weiss, for the festivities.

The guests — who took rapid COVID-19 tests upon entry — were invited into the large space, which included a retro diner modeled after her 8th birthday at Ed Debevic’s, the white BMW she received for her Sweet 16 and a life-size recreation of TAO nightclub, where the Kar-Jenners have celebrated many birthdays.

Rob Kardashian at Kim's Birthday Post-Weight Loss
Courtesy of Keeping Up With the Kardashians/YouTube

Although it didn’t look like Rob appeared at the actual event, the 33-year-old did attend the taping of her birthday special. Due to coronavirus restrictions, the mom of four — who shares kids North, Saint, Chicago and Pslam with husband Kanye West — thought her only b-day gathering would be filming their E! series.

Together, Kris, Khloé, Kourtney, Scott Disick, Kendall Jenner and Rob watched old home videos — many of them narrated by the late Rob Kardashian — looked back at some of Kim’s most iconic fashion moments and reminisced about her relationship with Kanye.

“Remember when they called you guys ‘Kimye?'” Dream‘s dad joked.

Rob Kardashian Shows Off Weight Loss on 'KUWTK'
Courtesy of Keeping Up With the Kardashians/YouTube

Rob has been making big strides toward his goals in recent months, having shown off his dramatic weight loss at Khloé‘s birthday party on June 28. After he flaunted his slimmer figure, KoKo spoke out about how proud she is of her sibling and admitted it brought her joy to see he was “feeling himself.”

He’s so handsome, he’s such a good person and I just love him,” the Good American CEO told E!’s Daily Pop about their close relationship. “And I love that he’s getting a positive response because it’s just gassing him up more. It makes him feel really good and confident. That’s all I want for my brother.”

A source exclusively told In Touch the Arthur George sock founder is “very happy doing his own thing and happy that his mom isn’t on him 24/7 anymore because he’s doing well.” Way to go, Rob!

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