Meanwhile, amidst the sandstorms of the northern frontier, a somewhat thin, dark-skinned, rough-faced boy with a hint of unnatural stiffness and a stubborn yet scholarly air about him, carrying a worn-out, bulging medicine chest, followed a newly replenished supply troop and laboriously entered the encampment of the left-wing vanguard battalion of the Zhenbei Army.

"Hey kid, what's your name? Where are you from? You look delicate and fair-skinned, not like you've ever suffered." The veteran in charge of registration glanced sideways at the boy who called himself "Anping."

“Reporting to the General,” Anping (An’an) deliberately lowered her voice, speaking with a slight Jiangnan accent, but without sounding effeminate, “I am Anping, from Jiangnan. My family… my family has been practicing medicine for generations, and we know a little about traditional Chinese medicine. Hearing that the soldiers in the northern frontier are fighting valiantly and lack medical care, I have come to offer my services and do my best.” Her expression was respectful, but her eyes were clear and firm.

"Jiangnan? Coming all this way to be a military doctor? It's not easy to have that kind of dedication." The old soldier muttered, writing the two characters "Anping" crookedly on the roster. "Alright, go report to the wounded soldiers' camp to see Medical Officer Li! Kid, let me remind you, this isn't your Jiangnan paradise of gentle pleasures, this is a place where real swords and bullets are deadly! Don't faint at the sight of blood!"

"Thank you for the reminder, General. I understand." An Ping bowed, slung her medicine kit over her shoulder, and walked deeper into the camp, where the air was thick with the stench of blood and the bitter smell of herbs. She straightened her back, suppressing her anxiety and guilt towards her family, her eyes filled only with the focused and resolute gaze of a healer facing the wounded. A new identity, a new battlefield, had begun.

An'an's departure cast a huge shadow over the children of the Prince's Mansion.

"Waaah... Does sister not want us anymore..." Ningning hugged Shen Yuewei's leg, crying so hard she could barely breathe, her little face scrunched up. In her hand, she was still clutching a small packet of dried, fragrant mint leaves that An'an had secretly given her before leaving, saying that she could smell them whenever she missed her sister.

"Sister is mean! She didn't keep her word! She promised to weave me the biggest grasshopper!" Yan Ge'er's eyes were also red as he angrily kicked at the pebbles on the ground, but as he kicked, tears started to fall again.

Kang Kang sat quietly under the veranda, holding the "Essentials of Medical Treatment" that An An often read. He flipped through a few pages but couldn't concentrate on a single word. He looked up at the gray sky to the north and asked Shen Yuewei in a muffled voice, "Mother, did Big Sister... really go to treat those wounded soldiers? Is it... very dangerous there?"

Shen Yuewei tenderly pulled the children close to her, gently comforting them: "Sister didn't abandon you. She's going to do something very important and remarkable. Just like... just like the soldiers who protect us, sister is going to protect the lives of those soldiers. She promised she would come back safely, and we must believe her."

Shen Huaiyu silently handed Ningning a clean handkerchief to wipe her tears and said softly, "Cousin An'an's medical skills are so excellent, she will definitely be alright. She is doing what she wants to do, and we should be happy for her."

Shen Huaijin had just returned from the martial arts training ground. Upon hearing the news, her mature-looking face was filled with worry: "Aunt, did Uncle send people to look for them? The northern frontier is so vast, with so many military camps, how can they possibly find them?"

Looking at the children's worried faces, Shen Yuewei felt a pang of sadness, but she could only force herself to stay strong: "Your father has already sent people to look for her, and he has also written letters to your Uncle Lu and your little uncle. An'an is very smart; she will protect herself. Before she comes back, we must take good care of the palace, make sure she studies hard, and practice her martial arts well, so that she can see a better home when she returns, okay?"

The children nodded as if they understood, but their longing and worry for their sister, like the gentle spring rain in Jiangnan, silently permeated every corner of the Prince's mansion.

A few days later, Marquis Lu Zheng of Zhenbei received a letter from Prince Jing, Xiao Chengjing, whose wording was extremely cryptic yet carried immense weight. After reading the letter, this veteran general, who had once dominated the battlefield, frowned deeply and paced around his tent several times with the letter in his hand.

"Nonsense! Utter nonsense!" Lu Zheng muttered, both angry at the audacity of the little girl from the Prince Jing's family and furious that this hot potato had been dumped on him. "A woman disguised as a man to join the army? If she's discovered... what kind of behavior is this! How could the Prince Jing be such a father!" Despite his words, a barely perceptible hint of admiration flashed deep in his eyes. Daring to venture alone into the lion's den for her ambitions—that courage was somewhat reminiscent of her parents back then.

"Someone!" Lu Zheng ordered in a deep voice, "Pass down the order: if any new 'boys' have recently arrived in any of the battalions, especially those with a Jiangnan accent and medical skills... keep a close watch on them! Especially the wounded soldiers' battalion! If you find anything unusual, report it to me immediately! Remember, it's 'closely'! Do not disturb them! And do not make a fuss!" He specifically emphasized the words "boys" and "closely".

Meanwhile, at the Longxi military base, the young general Shen Wensong was so shocked when he received his brother-in-law's letter that he almost jumped off his chair.

"What?! That girl An'an... ran off to the northern frontier? And even infiltrated the military camp?!" Shen Wensong slapped his forehead, his face full of headache and disbelief. "My little darling! She's incredibly bold! My brother-in-law is trying to kill me!" He quickly hid the letter close to his body, as if he were carrying a powder keg that could explode at any moment.

He immediately summoned his most trusted bodyguard captain and, in a low voice, instructed, "Go personally and discreetly inquire whether we have any new, exceptionally handsome, and medically literate 'junior doctors' recently arrived. The key is a Jiangnan accent! And bright, alert eyes! If you find one… bring her to me immediately, discreetly! Remember, absolutely no one can know! Especially not the military judge!" He paused for a moment, then added, "Be… polite! She's my own niece! I cherish her more than my own eyes!"

The captain of the personal guards looked bewildered, but still solemnly accepted the order: "Yes, Lieutenant General! I guarantee I'll find her! I guarantee I'll treat her with courtesy!" In his heart, however, he was wondering: Just who is this niece of the General? Why is the General so anxious?

The winds and sandstorms in the northern frontier remain fierce, and countless military camps, like giant anthills, silently operate.