Her name should be Cassidy, and she should have a nickname -- "Hop-along".

She got it when she was young, she was often 'getting into trouble' (from her parents' perspectives, anyhow) and intruding in things that weren't necessarily her business. Being a kangaroo, she was usually told to "hop along, now, little Miss Cassidy..." in such situations -- which, usually, she didn't take terribly kindly to, and in which, she was the only one who realized that there was a potential pun there. She found it funny but never let on, eventually doing it on purpose -- first to get the nickname, then because she found it both fun and interesting. Now she has a reputation as a neighborhood miscreant and everyone's sure she's going to turn out, when she gets old, as That One Nosy Neighbor Everyone Hates -- but hidden under that mohawk and mesh is a heart of gold that desperately wishes it didn't always feel like it had to keep guards at the door, and she has done some very good things for the people around her.

Only those who really know her well understand how "soft" she is inside, though, and that, in fact, that's her inner strength -- she's determined to be a decent person in the world. She's just had kind of a rough life. Her folks weren't all that well off, say lower-middle-class, and then one of 'em had an accident and couldn't work any more... a hefty dose of medical bills, plus the various government agencies that are supposed to help with that not really being of much use (as usual) meant that they had a rather short, steep drop into poverty -- and so most of her later childhood and her teen years were spent in places where there really wasn't much to do *other* than get into trouble.

Her parents do what they can to scrape by, now... the injured one manages to do a little on the side to augment their Disability payment (which they had to fight tooth and nail to get) but while they still talk every now and then about getting back to where they were, it's clear from their weary tones of voice and their phrasing, even if they don't outright say it (yet?), that they know it won't be in their lifetimes. As it is, Cassidy is working her way through college (quote marks optionally apply here; I could see her doing it that way!) because that's the only way she can afford it -- those medical bills absolutely obliterated her childhood college fund and just kept on going...

But having seen both sides of that world, she's determined to make the world a better place, and since she knows all too well (and from personal experience, no less) that the generally-endorsed-and-accepted ways of doing that, just won't ever work, she's going to do it *her* way. Hence the 'punk' look -- she's a rebel, through and through, for sure.

Cassidy and Mindy go back far enough that Mindy knows all of this, and asked Cassidy once why she didn't turn out a hippy, since she believes in a lot of that stuff. "Been kicked around too much, girl. The place I grew up would turn flower power kids into glitter paste." She takes a swig from a bottle of something cheap and strong -- the poor man's universal painkiller, in so many ways -- and then continues with a wry laugh, "I guess you could say some of us punks are hippies in Army boots. We're the ones that life made all tough and stringy inside."

Aussies forgive me, but I can't hear Cassidy's voice in my head with anything other than a quite thick New York City accent. Basically she's a young version of Dorothy from "The Golden Girls", only with twice the accent.

ngl I haven't given any thought to her backstory at all!
I like what you're written here! The name Cassidy does fit really well hehe
The only detail I want to contradict is that I don't want her to be Australian just because she's a kangaroo. I know you didn't mention her being australian, just wanted to put that out there.
I have thought of her accent, and I feel she has a Minnesotan accent (think Fargo by the Coen brothers). But I do dig New York accents, but I feel I've already head cannoned her accent as minnesotan. Maybe I'll change my mind as she develops, not sure!
Again, what you've written is beyond any intention of mine to give her a back story since I'm more focused on my main OCs. But if you wouldn't mind, I'd love to reference this for when she needs to appear in my comics :)
Thanks for writing this! I'm flattered you would feel inspired to give my character a backstory of your own! x3

Go for it! Believe it or not, I pulled all that together on the spot, no joke.

I have two fursonas and somewhere around two dozen characters (of at least slightly lesser personal importance) -- although I've never actually sat down and formally counted them out -- and over the past nearly 25 years or so since my first fursona (retired circa 10-15yrs ago), a whole multiverse and set of lore within it, just in terms of the history and structure of certain important species and such, including a bit of future-history for our own.

I'd love to chat... my PM box is always open ;) I don't bite and I try not to bark... lol...