Kourtney Kardashian and Travis Barker are over the moon as they finally exchanged vows and tied the knot in a lavish wedding ceremony in Italy. The reality star's famous family was in attendance to witness her milestone in life, except for one who's significantly missing.

Rob Kardashian ditched her eldest sister's wedding, and according to the Daily Mail UK, there's a deeper reason he chose not to attend.

A source spoke to E! News, saying the "Rob and Chyna" star didn't feel comfortable with all of the "spectacle" that went down during the nuptials.

The reality star has shied away from the limelight after the fall out of his relationship with Blac Chyna. He has also not appeared in recent seasons of "Keeping Up With The Kardashians" and their current Hulu series "The Kardashians."

"Rob didn't feel comfortable attending Kourtney's wedding because he doesn't like a spectacle," an insider close to the star revealed.

The source added that weddings are not Rob's cup of tea, and he didn't attend because he had become an "extremely private person" over the past years.

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To clarify if there's any bad blood between the siblings, the insider said Kourtney completely understood her brother's situation and didn't expect him to attend. She also knows that he supports her in her marriage with Travis.

This was not the first time Rob ditched a significant event in their family, as he also didn't attend Kim Kardashian and Kanye West's lavish wedding in 2016.

The TV star explained that his weight gain was the reason why he missed out on the big event.

"There were cameras at the airport on our trip there and I was very unhappy with the person I saw in all the pictures. I'm upset I missed my sister's wedding, but it was a personal decision," he said. (via People Magazine)

Regarding his absence from the reality series, a source said Rob likes to stay away from the limelight and "keep to himself." However, the insider clarified that he would make appearances at low-key events but doesn't want to have many cameras around.

The rest of the Kardashian/Jenner sisters, Kim, Khloe, Kylie, and Kendall, as well as mom Kris, were able to attend Kourtney and Travis' wedding.

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