The 30-year-old Keeping Up with the Kardashians star shared some Instagram pics from his stepsister's ex-boyfriend's wedding, writing: "Congrats @reggiebush !!! #bushwedding."
Jenner's attendance at Bush's nuptials may seem like a blow to Kimye as he did not attend their wedding this past May.
After being on and off for several years, Kardashian and Bush finally called it quits for good in March 2010. The 33-year-old reality star married rapper Kanye West, 37, in Florence, Italy this past May. Coincidentally, the couple's daughter North West was born just one month after Bush and Avagyan's little girl Briseis, in June 2013.