Last year Kim Jong Un's regime claimed to have successfully launched a new type of intercontinental ballistic missile which was of striking the US.
She has appeared prominently and is seen as the most influential woman along with Kim Jong Un's wife, Ri Sol Ju, in a country where family ties mean more than any title or rank.
The handshake between the sister of North Korean leader Kim Jong-un and South Korean president Moon Jae-in was highlighted as Games organisers reflected on the opening ceremony for the Pyeongchang Winter Olympics.
During the 2000s, the two countries' athletes marched together at the opening and closing ceremonies of several worldwide sporting events, including the 2000 Sydney Olympics.
American skaters Lana Gehring and Maame Biney enjoyed the presence of the North Korean supporters. "I don't think you talk geopolitics over speed skating", the second official said.
"I understand what Prime Minister Abe said is not to delay South Korea-U.S. military drills until there is progress in the denuclearization of North Korea". Senior political figures from North Korea and U.S. - two of the countries at the centre of the political row - were both present. The United States fought with South Korea and maintains tens of thousands of troops and an "ironclad" agreement to protect its ally. North Korea has tested a record number of missiles past year and has shown no interest in abandoning the country's nuclear program.
She is the first member of the Kim dynasty to visit South Korea, though her grandfather, Kim Il Sung, travelled to areas occupied by his troops south of what is now the Demilitarized Zone during the 1950-53 Korean War. US Vice-President Mike Pence, sitting a few seats away in the same Opening Ceremony VIP booth, looked stony faced as the scene unfolded.
The visual was important, a United States official said.
The two Koreas have a rocky and sometimes violent history at the Blue House.
As they shook hands, the North and South Koreans spoke briefly. The Korean news service reported that spectators who purchased tickets to Olympic events were unable to print their reservations until the site came back online Saturday morning.
Kim Jong Un has invited South Korean President Moon Jae-in to North Korea for talks in the first major development to stem from North Korea's participation in the Olympics, Moon's office announced Saturday.