Si Mi looked at Fu Zhen and Si Yan. Their expressions were so serious that the atmosphere became solemn!

She could not help but ask, "Who exactly is this X? Listening to you guys, he seems very mysterious!"

Si Yan also listened to Fu Zhen's suggestion very seriously. He frowned and thought for a moment. "Maybe President Fu is right! I was too rash and alerted the enemy!"

He looked at Si Mi and moved his chair closer to her. "This is a long story! Do you know the real cause of Mom's death?"

Si Mi looked at her brother and frowned slightly. "When Mom passed away in the hospital, I was there too! She died because of a heart attack! Didn't she?"

Si Yan shook his head. His expression was solemn, and the light in his eyes was bottomless. "That was just a one-sided proof from Gao Ping's hospital. It doesn't mean anything! Don't you find it strange that Mom suddenly passed away that year? She's been cooperating with the doctor's treatment the whole time. Moreover, the problem with her heart isn't as serious as the hospital says. What will definitely drag her down is her depression!"

"Mom... had depression?" Si Mi asked, somewhat surprised! She widened her eyes and looked at Si Yan!

Si Yan lowered his head. "Yes, her depression was even more serious than her heart disease! She had also been taking medication to control her condition. In the later stages, normal medication could no longer control her condition! Therefore, after many attempts to seek help, she finally listened to her attending physician's suggestion and tried to use a prohibited drug - K9!"

Fu Zhen looked at Si Yan. "What is the relationship between this attending physician and Gao Ping, who was still a senior nurse at that time?"

Fu Zhen was very good at organizing and analyzing information. He was very keen to grasp the key point of this matter!

"This doctor was still Si Long's friend back then. Mom thought that he was one of us, so she trusted him very much. She also cooperated with his treatment until he proposed to increase the dosage of the drug and add a new drug, K9! Only then did Mom realize that something was wrong! Her condition seemed to have improved, but in fact, she relied on a large amount of medication to control her condition. She was tortured by her illness and suffered several mental breakdowns!"

When Si Yan said this, his tone suddenly became urgent. "It was at this time that Si Long took advantage of her delirium and agreed to accept the K9 medication with using a family's opinion."

"When she woke up, she realized that the effect of the K9 drug was really more than ten times that of the usual drugs! She took it and tried to accept this 'new thing'! However, the situation after that was completely different from what the attending physician said. It went out of control, just like how drugs made people addicted to them. Mom couldn't get rid of it more and more! When she realized it, everything was already too much for her to take back!

Si Yan wiped the tears from the corners of his eyes and looked at Si Mi. "I know this because I found her diary in Mom's belongings! I hid it secretly! This matter is far from as simple as it seems. Why would a normal doctor ask a patient to try illegal drugs?"

"So you went to investigate this doctor, right?" Si Mi tried hard to digest the information and pressed her hand on her heart. "You didn't tell me this last time!"

"At that time, I couldn't bear to see you being deceived by Gao Ping, so I left out the information. I wanted to remind you to stay away from them!"

Si Yan said, "I did investigate. This doctor is indeed inextricably linked to Gao Ping. He is her senior in the same school. Although the two of them have different specialties, they once participated in a top-secret project in their research institute! No one knows the details! His crime was too serious, and Gao Ping was also involved!"

"So you've been chasing Gao Ping, and at the same time, you've been paying attention to K9!" Fu Zhen said.

Si Yan lowered his head. "Gao Ping thought that she could wash her hands clean in that incident, and all the blame was shouldered by that doctor! On the contrary, she was innocent and successfully became Mrs. Fu!"

He laughed mockingly. "Isn't it too obvious? In a case, whoever is the final winner will be the murderer! As long as I can find out the source of the doctor's K9 at that time, I can pin the crime on her!"

"This X is extremely important! I must take him down!" Si Yan looked at Si Mi. "You can understand, right? Mom's revenge is on us!"