Another silly headcanon for Spider (inspired by me finding all my baby teeth that my mom keeps in a box for some reason):
Every member of the Sully family has one or more of Spider's baby teeth. It starts all because of a misunderstanding.
Norm had told Spider that his front bottom tooth was set to fall out soon, something Spider didn't understand because Na'vi children don't lose their teeth. Norm skips over explaining that Spider once again is not Na'vi, and instead tells Spider to just bring the tooth back to Hell's Gate if it comes out while he's playing outside. When asked why, Norm and Max explained that he needed to keep his tooth so that the tooth fairy could come and give him a gift in exchange for his tooth.
Now, Spider has no frame of reference for anything that they're talking about. All his 5-year-old brain gets is that somewhere out there, there is a human who steals kids' teeth, and he's terrified.
Later that day, Spider goes careening through the forest and bursts into Mo'at's pod where everyone tends to eat lunch, yelling in broken Navi about a theft coming to take his teeth.
Jake immediately understands what he talking about, but heās too busy laughing to properly explain. By the time he catches his breath, Moāat, Neytiri, and the kids have both been thoroughly convinced that there is a theft among humans taking childrenās teeth. In a rare moment of compassion towards the human boy, Neytiri assures him that she will protect his teeth. Jake decided not to tell them the truth and just let events play out.
Spider winds up losing his tooth later that day, roughhousing with Loāak, who takes great pride in telling everyone he will protect Spiderās tooth from this "tooth theft".
And thus brings the saga of the Sully family all coming into possession of Spiderās baby teeth (to keep safe from the tooth theft, of course).
Loāak gets Spiderās first baby tooth but winds up with 10 over the years (much to Kiri and Neteyamās envy). To be fair, Loāak is responsible for most of them falling out anyway. He takes all of them after Spider loses his last one and weaves them into an intricate armband that he wears during festivals and special events to always have a piece of Spider with him.
Kiri has 3 of his baby teeth, the majority of which she keeps in a wooden chest she made for all her most prized possessions. The first one she got was one of Spiderās left upper canines that she wiggled out herself after nagging Spider about it for days. She used it as a charm on her anklet and never took it off.
Neteyam also has 3 baby teeth - all molars. 2 fell out simultaneously while Spider was eating Pali jerky. The first, however, fell out just before their first hunt. Spider had been wiggling it all night, and it fell out while Jake was checking their gear. Spider handed it to Neteyam, declaring that their hunt would be fruitful because that was his lucky tooth. Spider never shares what about the tooth made it lucky, but they both caught their first yerik that day, so Neteyam takes it with him whenever he goes hunting. After the humans return, he encases the tooth in amber into his bow, hoping that its luck will protect him in battle.
Tuk, Jake, Neytiri, and Moāat each have 1, with Tuk getting the last baby tooth Spider ever lost. It was his left upper front tooth, and like Loāak, she was the cause of it falling out because she accidentally head-butted him while he was eating with a cannula. Thankfully, he didnāt choke on it, and now Tuk has it on her songcord, representing Spider as her brother.
Jake gets his tooth gifted to him by Spider after it falls out. Itās his other front tooth that Spider wiggled out himself and decided to give to the man because Loāak was annoying that day. Jake denies wholeheartedly that he cried afterward. He, too, adds it to his songcord on Spiderās 13th birthday, declaring that Spider is now a man since all his baby teeth are gone.
Moāat has the second baby tooth Spider ever lost because she had to pull it out herself. Spider had fallen and chipped the tooth, causing extreme pain. Since Hellās Gate has no dentist, Moāat pulled the rest of the tooth out herself while Norm fretted behind her. Spider bounced back quickly, proudly showing everyone the new space in his mouth. Moāat keeps the two pieces of Spiderās bottom front tooth and fashions them into earrings that she wears on his birthdays.
Spider gifts Neytiri her tooth, a small lower molar he lost while eating caramel that one of the scientists in Hellās Gate made. He gives it to her for the human holiday called Motherās Day but does it at the end of the day, right before Norm comes, to avoid rejection. Once he's older, Spider realizes he never saw the tooth again and figures she either threw it away or gave it to one of the kids to add to their collection. In reality, tucked away in a small box in their family pod, sitting next to the only picture Neytiri has of her sister, the last arrowhead her father ever made, and Jake's old dog tags, lies Spiderās baby molar.