Jaejoong took to his social media on March 24 to announce that a new member has joined his niece's family, revealing that he will soon be a granduncle in 10 months. He shared a photo of himself playfully puckering his lips with his eyes closed, humorously calling himself "the first idol grandpa." Being the youngest among his siblings, Jaejoong has a total of 13 nieces and nephews.

In a past appearance on KBS 2TV’s 'Stars' Top Recipe at Fun-Staurant' in 2023, Jaejoong gave viewers a glimpse into his family life. His eldest sister, who is 20 years older than him, hinted at the upcoming addition to the family by mentioning that he would soon become a granduncle.

Recently, Jaejoong established the entertainment agency iNKODE Entertainment, where he is actively involved as a producer and entrepreneur. The agency represents artists like child actress Oh Ji Yul, actors Jung Si Hyun, Lee Ji Hoon, Kim Min Jae, and Nicole. Jaejoong also introduced the seven-member girl group SAY MY NAME last year in his role as a producer. Additionally, he shared that his agency spends 20 billion KRW annually to manage two idol groups.