Mutant Sea Turtles - Jackson (updated)

'Nother old TMNT OC, never really fleshed him out properly last time.
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Species: Kemp's Ridley Sea Turtle

Name: Jackson
Nickname: Jax or Jackie

Character:
Has the gift of gab/a way with words, conversationalist. Approachable, that friend you go to for venting life problems. 
He's got a pretty singing voice kind of like Enrique Iglesias's and his sister Ana is always encouraging him to sing with her.
Passionate about animals and the natural world, is a conservationist, as much as a secret mutant can be.
His personality has no place in the Foot Clan and he knows it, pretends to be a hardass for appearances. Will defect at the first opportunity he can do so safely.

Backstory:
Jackson is the runt of the sea turtle siblings - probably the only male to hatch from the nest - being closest to the surface during incubation. He's always been small, weak and sickly, and his initial mutation did not particularly change that.
Next to his sisters he looked small and frail, and was more often than not sick with something. His sisters are very protective of him because of this, and also because the foot soldiers abused him a lot as well - he could not fight very well, though he tried so hard he just wasn't strong enough. 
Eventually he was injected with a very diluted mutagen by Baxter Stockman as an experiment, triggering a slow, year-long secondary mutation. He now dwarfs his sisters as a hulking mass of hormonal muscle and shell.