Rob shared several photos from the fete on Twitter, including a picture of himself holding Dream. The doting dad appeared much slimmer in the snapshot, which Kim Kardashian also posted to Instagram Stories.
"March Madness," he captioned the photo.
Rob Kardashian, whose birthday falls on St. Patrick's Day, also posted a picture of Dream using a shamrock filter.
"Happy birtbday to me :)," he wrote, adding two shamrock emojis.
He shares Dream with ex-fiancee Blac Chyna, from whom he split in 2017. Chyna surprised fans by wishing Rob a happy birthday on Instagram Stories following months of conflict.
"Happy Birthday Rob from Dreamy and Chy," she captioned a photo of herself with him and Dream.
Kim Kardashian also marked her brother's birthday in a post online. The 37-year-old television personality welcomed her third child, daughter Chicago West, with husband Kanye West in January.
"Happy Birthday to my brother Rob!!! I love you so much and wish you all of the happiness in the world! I love raising our kids together, you're the best dad and friend! Can't wait to celebrate today!" she tweeted.
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