SEOUL — The daughter of North Korean leader Kim Jong Un, Kim Ju Ae, is believed to have a younger sibling, South Korea’s National Intelligence Service (NIS) has said, providing fresh information about the secretive ruling family.

The NIS said it currently assesses that Kim Ju Ae is being groomed as her father’s successor and has a younger sibling whose gender remains unknown.

South Korean intelligence authorities have previously assessed that Kim Jong Un has three children, although uncertainty has persisted over their birth order and the identities of the other children.

Kim Ju Ae was first publicly introduced in 2022 when she appeared alongside her father during an event marking the launch of an intercontinental ballistic missile. Since then, she has increasingly accompanied Kim Jong Un at major political, military and diplomatic events.

North Korean state media have also increasingly used prominent descriptions for Ju Ae, including “the beloved child” and “a great person of guidance,” language that has heightened speculation about her future role in the country’s leadership.

The NIS said it is still working to verify whether Kim Ju Ae has an older brother. However, the agency said that even if such a sibling exists, it does not currently assess him to be in a position to succeed Kim Jong Un.

The latest assessment adds to growing international attention surrounding Kim Ju Ae and the question of succession in North Korea, where power has remained within the Kim family for generations.

The North Korean government has not publicly provided detailed information about Kim Jong Un’s children, making South Korean intelligence assessments one of the main sources of information about the country's ruling family.