Kim Jong Un took his daughter to a meeting with missile scientists and called her his 'most beloved' child.
Now only aged about 10, but her new, bold photos are deepening the debate over whether she's being primed as a successor.
She is believed to be Kim's second child named Ju Ae and was first unveiled to the outside world last weekend in state media photos.
They showed her watching North Korea's intercontinental ballistic missile launch the previous day with her parents and older officials.
Wearing a white puffy coat and red shoes, she was shown walking hand-in-hand with Kim past a huge missile loaded on a launch truck and watching a soaring weapon.
North's official Korean Central News Agency mentioned her for the second time, saying she and Kim took group photos with scientists, officials and others involved in what it called the test-launch of its Hwasong-17 ICBM.
KCNA described her as Kim's "most beloved" or "precious" child, a title which has more honours than her previous description of "(Kim's) beloved" child.
State media-released photos showed her in a long, black coat holding her father's arm as the two posed for a photo.
Looking like her mother Ri Sol Ju, who wasn't visible in any of the photos, she had a more mature appearance than a week ago when she was last seen in public.
Some photos showed the pair standing in the middle of a line of uniformed soldiers before a massive missile on top of a launch truck.
Others showed her clapping, exchanging handshakes with a soldier or talking to her father as people cheered in the background.
Ankit Panda, an expert with the Carnegie Endowment for International Peace said: "This is certainly striking.
"The photograph of Kim Ju Ae standing alongside her father while being celebrated by technicians and scientists involved in the latest ICBM launch would support the idea that this is the start of her being positioned as a potential successor.
"State media underscoring her father's love for her further underscores this, I think.
"Finally, both of her initial public appearances have been in the context of strategic nuclear weapons - the crown jewels of North Korea's national defense capabilities. That doesn't strike me as coincidental."
After her first public appearance, South Korea's spy service told lawmakers the girl pictured was Kim's second child aged about 10 and whose name is Ju Ae.
The National Intelligence Service said her looks matched information that she is taller and bigger than other girls of the same age.
It also said that her unveiling appeared to reflect Kim's resolve to protect the security of North Korea's future generations in the face of a standoff with the United States.
South Korean media previously speculated Kim has three children - born in 2010, 2013 and 2017 - and that the first child is a son and the third is a daughter.
She is likely to be the child who retired NBA star Dennis Rodman saw during his 2013 trip to Pyongyang.
After that visit, Rodman told The Guardian he and Kim had a "relaxing time by the sea" with the leader's family and he held Kim's baby daughter, named Ju Ae.
North Korea has made no mention of Kim's reported two other children. But speculation that his eldest child is a son has led some experts to question how a daughter can be Kim's successor given the deeply male-dominated, patriarchal nature of North Korean society.
Soo Kim, a security analyst at the California-based RAND said: "We've been told that Kim has three children, including possibly a son.
"If this is true, and if we assume that the male child - who has yet to be revealed - will be the heir, is Ju Ae truly Kim's most `precious,' from a succession standpoint?"
"I think it is too early to draw any conclusions."
She said that Kim Jong Un may think the unveiling of his daughter is an effective distraction while conditioning Washington.
For others living with the North Korean nuclear threat, she said, "the spectacle of Ju Ae appears to eclipse the intensifying gravity of North Korea's nuclear and missile threat."
She added Kim Jong Un may also want to tell his people that nuclear weapons are the sole guarantor for the country's future.
Kim Jong Un called the recently tested Hwasong-17 "a great entity of strategic strength" and ordered officials to further build the country's military capability to a "more absolute and irreversible one."
The weapon is designed to strike the US mainland was part of a barrage of missile tests which were meant to issue a warning over US.
And South Korean military views as an invasion rehearsal.
Leif-Eric Easley, a professor at Ewha University in Seoul said: "Kim may be signaling to other North Korean elites that he is mentoring his daughter for a role in the leadership.
"Giving her such an early and public start is unusual but reflects the historical and political significance Kim attaches to a nuclear missile that can reach the United States"
Analyst Cheong Seong-Chang said that Kim Jong Un cannot make his son his successor if he thinks he lacks leadership.
Cheong said Kim may be preventing potential pushback choosing a daughter as a fourth-generation leader.
He is thought to have brought her to a successful ICBM launch event to help public loyalty toward him be carried on smoothly to his daughter.
Cheong said: "When a king has many children, it's natural for him to make his most beloved child as his successor.
"Kim Ju Ae is expected to appear occasionally at Kim Jong Un's public events and take a succession training."
