Water Siblings

Water Siblings is the Family ship between Sokka and Katara from the Avatar: The Last Airbender fandom.

Canon
Sokka and Katara are brother and sister, born to Hakoda and Kya one year apart from each other. They were shown looking after each other throughout the years. Sokka began to see Katara as his mother figure after their mother Kya passed away and Katara took on the role of watching out for the family and performing their tasks. When their father Hakoda left to fight in the war, he asked Sokka to stay behind and look after Katara. Sokka did not understand why he could not join his father and had to watch over his sister but his father assured him that he would understand one day and continued to look after his sister.

Sokka eventually took Katara out on a fishing trip in order to teach her how to fish. Katara caught a fish with her waterbending before dropping it on her brother's head. Sokka told Katara to stop playing with 'magic water' before she reminded her brother that bending was not magic but an ancient art. Sokka then almost crashed into some icebergs, prompting Katara to shout at him to watch out before they became stranded. Sokka blamed Katara for their troubles, stating that a girl always messed things up. Katara became angered with his sexism and accidentally destroyed an iceberg in her anger, which caused her to accidentally reveal a boy named Aang who was trapped inside of a submerged iceberg.

Katara was happy to meet Aang as she had never met another bender before while Sokka was more wary of his presence. When Aang and Katara accidentally triggered a Fire Nation booby trap, Sokka had Aang banished and guilt-tripped Katara into staying with them. However, when Aang turned himself into the Fire Nation in order to protect their village, Katara insisted on going after them, and Sokka had already agreed to help her. Katara was excited that Sokka has a heart and embraced him. Upon learning that Aang is the Avatar, Katara and Sokka decided to travel with him while he mastered the elements, which Katara suggesting that Sokka would get to beat up some Fire Nation soldiers, which he agreed that he would enjoy.

Katara and Sokka continued to support each other and bicker occasionally during their journey. This was shown when Katara was sewing Sokka's pants and threw them at him when they were still unfinished after he made a comment about gender roles and stereotypes. Sokka was later rude to the Kyoshi Warrior leader Suki, who threatened to feed them all to the Unagi, and Katara attempted to apologize on her brother's behalf. When Aang accidentally burned Katara while learning firebending, Sokka immediately came to his sister's aid and shouted at Aang before running off with her. When Katara revealed her ability to heal and claimed that she always knew how, Sokka questioned why she did not use during certain situations throughout his childhood, such as when he had two fishhooks stuck in his hand.

Sokka was shocked by Katara dating Aang after the Hundred Year War. He accidentally walked out into them kissing and they got into an argument, which Sokka complaining that he gets the 'oogies' every time he sees them together. Despite this, Katara and Sokka remained close and journeyed back to the Southern Water Tribe together after being gone for two years. They found that their home had changed greatly and Sokka accepted the change a lot sooner than Katara did. Sokka passed away by the time that Avatar Korra left the Southern Water Tribe and Katara spoke of him when encouraging her children to spend more time with each other.

Fanon
Water Siblings is one of the most highly regarded familial relationships in the fandom, rivaling only Irko. Despite their small bickering, which many consider to be typical of siblings and healthy in some cases, they are often considered to be one of the healthiest sibling relationships in the fandom. Fans of Avatar often debate which siblings in the Avatar universe had the best relationship and Sokka and Katara's relationship are often among the candidates that fans consider for the best sibling relationship.

Despite their status as siblings, there are a small number of fans who ship Sokka and Katara romantically. This is possibly due to the fact that Katara and Sokka disguised themselves as Aang's parents in The Headband. Sokka disguised himself as a man named Wang Fire while Katara pretended to be a woman named Sapphire Fire and fans were amused by this and thought that Katara was also pretending to be pregnant in that disguise.

Fandom
FAN FICTION