"I'll ask you once and only once; WHERE IS MY MOTHER!" Enraged at his father Ozai, Zuko shouted with abundant anger, his face red with rage and his glare could have dug into the soul of his father. Yet Ozai's had no response.
Zuko was ready to do the very thing Aang failed to do: kill his father. Zuko stretched his arms while Ozai watched in fear and right at that moment, Katara walks in and stops. In shock she shouted "ZUKO STOP! Revenge is never the answer, just as I could not kill the man who murdered my mother, you can't do the same."
Zuko considered his friend's inspirational words and left his father in the cell where Katara stood almost paralyzed at the thought of what could have happened if she was not there. Zuko decided to make a trip by his uncle. Iroh could only tell him that his mother was lost and only his brother Ozai would know where she might be. Zuko made an interesting trip to the mental health facility where Azula was being treated, Zuko thinking "Ozai tells Azula everything.".
The moment Zuko stepped in Azula's room Azula laughed and teased "Zuzu you don't look so good" then attacked Zuko yelling "BEING FIRE LORD IS TOO MUCH PRESSURE!" Zuko didn't waste anytime in showing Azula her place. He then asked, "Where's our mother?"
Azula could tell her brother was serious and revealed one thing to him about Ursa that Zuko seemed to forget, "Ursa was banished from the Fire Nation. She probably would go the furthest place from here!"
With those words Zuko knew exactly where his mother was. Zuko allowed his sister to come and see their mother at this point in time Azula's mental issues were growing worse just at the thought of meeting her mother again. Katara accompanied them to make sure Azula would not harm Zuko. When Appa took them to Ba Sing Se he asked for Ursa and from behind a tent you could see a flood of tears on a proud mother's face Zuko cried and his mother rushed to him first and then Azula's problems aroused.
Sobbing uncontrollably Azula screamed in rage "YOU LOVED ZUKO BETTER!"
"Azula I love you and I always have." Ursa said passionately
At these words Azula struggled to keep control but her efforts were to no avail. She then spread fire around her mother and brother sobbing and screaming "LIES! YOU WILL ALL BURN!!!!"......