Kylie, 16, brought Jaden, 15, as her date to her half sister's wedding and they were spotted having a grand time celebrating the nuptials, reported E!Online.
The longtime friends were reportedly seen getting cosy during the lavish reception following the ceremony at the Forte di Belvedere in Florence, Italy, on Saturday.
Will Smith's son was also seen heading for the airport with Kylie and the rest of the Kardashian-Jenner family after the celebration.