Zuko might become overprotective. His previous respect for Katara's abilities might be overshadowed by his fear of her getting hurt again. This could cause some friction in their relationship as Katara might not like being overly protected. For instance, he could try to stop her from going on dangerous missions.
Their relationship could take a more romantic turn. The vulnerability of Katara when she's hurt might make Zuko see her in a different light. He might start to develop romantic feelings for her if he hadn't already. And Katara, seeing his concern, could also start to feel something more for Zuko. This new dynamic could lead to a whole new chapter in their relationship in the fanfiction world.
Zuko could become extremely angry. If someone has intentionally hurt Katara, he would likely seek revenge. He has a strong sense of justice, and Katara is someone he cares about. So, he would not let the person who hurt her get away easily. For example, he might use his firebending skills to confront the perpetrator.
In some fanfictions, Katara might hurt Zuko physically during a fight. For example, if they have a misunderstanding and their elemental powers clash, Katara's waterbending could accidentally strike Zuko and cause him harm.
It would likely become more complex. They would have to rely on each other more as parents. Their love might deepen as they share the experience of raising a child together.
Often, their relationship deepens. There's a new level of closeness as they face this unexpected situation together. Edward becomes more tender and caring towards Bella, always making sure she's comfortable.
Their relationship would likely become more intimate and complex. They would have to rely on each other more, sharing a bond that goes beyond their previous friendship or alliance. Zuko would probably become more protective of Katara, and Katara would trust Zuko with her vulnerability during pregnancy.
Their relationship would likely become more intimate on an emotional level. They'd have to rely on each other more. Zuko would be more protective of Katara, and Katara would be more open with Zuko about her feelings and needs during the pregnancy.
For Zuko, the training might change his view on bending. Instead of seeing it as a tool for power or revenge, he starts to see it as a form of art, like the dragons do. This could make his firebending more refined and less aggressive. For Katara, she could become more confident in her abilities. The dragons' power and wisdom might inspire her to be more creative with her waterbending, perhaps finding new ways to heal or attack.
In some cases, the anger could be a catalyst for a more romantic development. Aang expressing his strong emotions might make Katara realize the depth of his feelings for her. Or it could be the other way around, Katara's reaction to his anger could make Aang see her in a new light, leading to a shift in their relationship dynamic towards a more romantic one.
In a lot of 'Katara gets hurt' fanfictions, she can be hurt in combat. For instance, in 'Katara's Battle Wounds', she's fighting against a group of bandits and gets slashed by a sword. However, there are also fanfictions where she gets hurt due to accidents. In 'Accidental Hurt to Katara', she trips over a hidden root while running and breaks her leg. And in some more complex stories like 'Katara's Mysterious Hurt', she's affected by a strange curse that slowly weakens her and causes her pain.
They would become more protective of each other. Since they now have a baby together, any threat to one of them would be seen as a threat to their family unit. Zuko might become even more determined to keep Katara safe, and Katara would do the same for Zuko. Their love would grow deeper as they share the joys and challenges of raising a child. They would also have to communicate more effectively, especially when it comes to making decisions about their baby's upbringing.