Aaron Watson was originally a guest character as the son of Ariel Watson, a character which joined the Main Cast midway through the first season. Aaron was kept on even after Ariel's death and became a regular in season two and has appeared regularly ever since.
Aaron first arrives in Crystal Town as his mother Ariel and he turn up at her cousin's Tina's house as they have nowhere else to stay. "(Nowhere To Run)". Tina was reluctant to let them stay as she was currently having problems with her husband David and she felt Ariel and Aaron moving in would only make things worse but she allowed them to stay until they got back on their feet. Aaron soon became friends with Tina's son Robert and told him that he was jealous of him because his mum cared about his well being and what he did with his life whilst Ariel did not have the same worries for Aaron. "(To Make Things Worse...)". Aaron's friendship with Robert grew stronger as he comforted him after David walked out on the family, ending his marriage with Tina. "(No Good Deed)".
Aaron cuts his hair and dyes it blonde for a party and invites Robert to go with him, he is reluctant at first but Aaron forces him to go and he takes him shopping to pick out some clothes for the party. "(For My Family)". When returning home that night Robert pleads with Aaron not to drive as they have been drinking but Aaron refuses, they then approach a nightclub where Tina and Ariel happen to be having a girls night out with the other ladies in the neighbourhood, the two row and Ariel stops dead in the middle of the road to yell at Tina and Aaron who is speeding, hits her, knocking her over the car. Aaron goes to pull over but Robert tells him to drive off as he does not want to be arrested. They are both unaware that they had hit Ariel and that Tina had saw them. They return home and are informed by Tina that they had hit Ariel and killed her. Tina however promised Aaron that she would lie to the police to protect him from going to prison as she had promised Ariel whilst she was dying that she would take care of him for her. "(The Message From The Gone)" "(Ten Simple Rules)".
Six months following his mothers death Aaron still struggled to cope with what he had done. He remained to live with Tina and Robert but unlike Robert who began universty Aaron struggled with his guilt so badly that he didn't do anything which annoyed Tina who continued to try to get Aaron to continue as normal and do something with his life. This caused the two to snap at each other about Tina not getting along with Ariel and the fact that Aaron was the one who killed her. Aaron also began to have nightmares about the night his mother died. "(Six Months On)". Aaron later formed a crush on new neighbour Marie and stole her mail in an excuse to go and talk to her, he became embarssed however when Marie turned him down because of his age and the fact she had a girlfriend - Yasmin. Yasmin saw Aaron flirting with Marie and confronted Tina angrily over it demanding her to tell Aaron to stay away from her girlfriend. "(Behind Bars)".
Tina later treated both Aaron and Robert to dinner at Bruce's Italian Restaurant. "(Fallin' Florida)". When they returned home from dinner and all went up to bed both Aaron and Robert was unaware that Tina's ex-husband David had returned home after losing his job and house. "(Welcome To The Family)". Aaron is later present when Tina tells him, David and Robert that neighbour Jean Smith is to move in for a while due to her violent husband. Aaron and David tell Tina they don't mind her moving in but Robert is strongly opposed to it. "(Men? Who Needs 'Em!)". Aaron later confronts Robert over his rude and bullying attitude to Tina, Robert responds by insulting Ariel which causes Aaron to attack him. David breaks up the fight and tells Robert that he wants him out of the house due to his behaviour and disrespect for his family. "(Ho Ho The Witch Is Dead)".
Some time after Aaron attends Sharon Grey's funeral with Tina and David. "(Stabbing Pains)". Aaron is soon tasked with babysitting Marie's daughter Alice, the pair sneak into the living room when asked to go upstairs by Tina and Megan as they were having a private conversation, Aaron gets caught however whilst Alice saves herself and runs back upstairs. The pair are later with Tina and Megan when a huge earthquake occurs and the four flee down to the basement. "(Not A Good Day)".