Miao Dagui had worked hard for many years, and his health was already poor. His sudden, severe illness was the result of his chronic conditions flaring up, triggering the acute cerebral thrombosis that caused him to collapse.
It was a stroke of luck that he didn't die instantly, but instead held on until Shen Nian arrived.
If Miao Dagui had been suffering from some other malignant condition, like cancer, the current Shen Nian might not have had the ability to help.
However, given Miao Dagui's current condition and the level of Spiritual Power she now commanded, Shen Nian was confident she could at least improve his state, even if a full cure wasn't possible yet.
As for what came after, that would depend on how his body was cared for during recovery.
Although Shen Nian had the Shen family brothers keep everyone at a distance so she wouldn't be disturbed, she hadn't kicked them all out. Anyone who wanted to watch could still see what she was doing.
