But even if Zhang Tianhuo could do it, you still could not allow such a thing to happen. No matter how the books tried to conceal it, these people all shared one trait: they could only succeed in refining it by using secret arts that damaged their life essence—lifespan.
Zhang Tianhuo still had a bright future ahead of him, so you ought to consider raising his cultivation realm now. Even if you had to pile treasures upon him, you needed to swiftly push Zhang Tianhuo into the True Immortal Realm. Whether he attained an upper third-grade Dao Fruit did not matter, because beyond the True Immortal Realm, there was nothing more you could do for him.
Among your three sons, only Ye Chen put your mind somewhat at ease when it came to the Immortal King Realm. Judging by his current cultivation progress and the talent he had displayed, there should not be much of a problem. As for Ye Xing and Ye Ping'an, you were not very confident that either could condense a Dao Fruit above second grade, let alone verify the Dao. They would most likely still need your help.
Zhang Tianhuo's talent was far inferior to those three, so all you could do was let nature take its course. Such things could not be forced, even with Dao treasures to aid him. With poorer talent, using external resources to raise one's cultivation realm required resources that increased exponentially.
This Second-ring Dao Pill Zhang Tianhuo refined was called the "Blood Spirit Nourishing Dao Pill." It was a type of Breakthrough Pill that could help living beings in the early stages of the True Immortal Realm—those newly entering the realm, in the First Stage of the True Immortal Realm, the True Immortal Second Realm, and so on—rapidly break through