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While Kim Kardashian and Kanye West were welcoming their daughter into the world, Kardashian's ex, NFL star Reggie Bush, was celebrating his own bundle of joy.

The 28-year-old Detroit Lions running back posted a cute Father's Day photo of him holding his month-old daughter, Briseis, along with the words, "Enjoying my first Father's Day with my family! #blessed"

The baby's mother, dancer Lilit Avagyan, is of Armenian descent, just like Kardashian, and looks strikingly similar to the reality star. She and Bush were together for less than a year when he confirmed her pregnancy in October 2012 - just months before Kardashian, 32, announced her pregnancy.

Bush and Kardashian dated off and on for several years before calling it quits in March 2010.

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Following the birth of his daughter on May 6, Bush told Us Weekly, "I look at Briseis and I can't believe that she is mine. There's still that element of I can't believe this came from me."

Kardashian gave birth to a baby girl on Saturday.

"She's doing great and she's beautiful," Kris Jenner, the Kardashian matriarch, 57, told HLN Sunday night at the Daytime Emmys. "We're all fine. We're all good and extremely happy and thrilled for the new baby."