The Sages had also informed Sozin of the impending arrival of a comet - one which would grant the firebenders a massive increase in power. Sozin began moving troops so that once the comet arrived, they could launch a devastating first strike against the other 3 nations. The opposition, reeling from the surprise attack, would have a hard time getting back on its feet to fight back. At least, not until it was already too late.
He worried, in spite of it all, because he could not deny that he was getting on in years. Already an octogenarian, Sozin feared he would not be able to last long enough to ensure an insurmountable advantage in the war. He feared that without his leadership, the war effort would disintegrate. And he worried about his continued lack of an heir. He mulled these problems over in his mind as he marked off the remaining days before the comet's arrival.
"My Lord!" a messenger shouted, rushing across the throne room. "Wonderful news!"
"What is it?" Sozin asked, scrutinizing the messenger.
"It's your Lady Ilyra! She is with child!" The calendar scroll in Sozin's hands clattered to the floor.
"She... she is? I'll finally have an heir?" Sozin stared ahead blankly. The messenger smiled at the Fire Lord as he pushed past and silently headed to his wife's chambers. As he threw the doors open, she turned and smiled at him, tears in her eyes, hands on her stomach. Wordlessly, he drew her into an embrace and kissed the top of her head.
The next nine months seemed to fly by. Sozin's first strike was executed perfectly, and the generals reported their assurances that the airbenders had been completely wiped out. The firebenders hammered away at the Water Tribes, looking for signs that the Avatar had been reborn. Several weeks passed, however, with no word of a new Avatar. Some began to speculate that the Air Nomad Avatar wasn't dead after all. Some believed that the cycle had been broken, and the Avatar was never reborn into the Air Nomads. Either way, it was clear that the Avatar wasn't going out of his way to avert war.
Once Sozin was confident in his generals' abilities to carry out the initial plans for his conquest, he focused his attentions on his wife and newborn child. He felt somewhat guilty, being a father nearly old enough to be the child's great-grandfather. He was relieved, however, that it most likely meant no surprises in terms of his succession. The new prince was named Azulon, and was doted on day and night by parents and palace staff alike. He showed impressive talent in his firebending lessons, something which made Sozin beam with pride, and reminded him more than a little of himself. Azulon excelled in his military lessons as well, and showed an intense interest in his country's progress in the war. Sozin was confident the boy would make a fine Fire Lord when the time came.
The time came sooner than Sozin, and Azulon, had hoped. Only twenty years after the war began, Sozin's body finally gave out. Well-educated and trained though he was, Azulon felt unsure about suddenly having an entire country dumped in his lap. He was still quite young, and his arranged marriage had not even been finalized before his parents passed away. He was forced to put that issue on hold while he familiarized himself with the generals and admirals at his command, and the tactics they were employing in the war. And as the newly crowned Fire Lord set about planning the future of his country, he remained completely ignorant of the foreboding scroll hidden behind the tapestry in his late father's chambers.