Taking my hand at a couple of guesses cause I've mostly just been lurking but I got some thoughts
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I think either tree cat or blanket kitty belongs to Aurora Storm but I'm leaning more to tree cat (like @lotusmoon9's guess)
So what we know (also added some extra things I found):
- Aurora's dress-up included a hidden rainbow lorikeet feather which might imply that her cat either is a bird OR a place birds hang out a lot.
- Enjoys sunlight
- Loves showing off during sunrise and sunset
- Hidden "aussie aussie aussie" in bottom of signature so the cat is related to Australia
- Mentions of plants "planted two more hints", "plant more trees"
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Recent dress-up referencing gum trees(? The lyrics in the description are from "Home Among The Gum Trees" by John Williamson)

SO I looked a bit into rainbow lorikeets and found out they like eucalyptus trees
(which are a species of tree that is mostly native to Australia and is also a gum tree)
And since they are a tree, obviously they'd enjoy the sun
I think the smoke might be referencing forest fires? Maybe referencing eucalyptus trees adaptation to fire?

I'm not sure if it's been pointed out yet but this kitty looks to have line edits on its sides?
Personally, I think it's a pair of folded wings so I'm going to run with it but I could be way off.
I'm thinking this kitty might be inspired by rainbow lorikeets as the chest fur and shoulder markings make me think of a bird and also the wings.
Aurora mentioned that her cat enjoys sunrise so maybe this kitty wakes up early (hence why they look tired) every morning to see the sunrise?
Also the mention of liking to show off fits as rainbow lorikeets aren't shy and are rather enthusiastic. I'm thinking that this cat will grow up to be more extravagant and lively.
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Oddity's and Wobbuffet's cat are 50/50 for me. If the witch cat isn't Oddity's outcome then I think it's Wobbuffet's and if Wobbuffet's outcome isn't the ice cream cat then I think it's Oddity's.
I'm stuck up on this one belonging to Oddity due to how much story I feel it has to it.

- It fits into DnD with the costuming (D20 roll)
- Is pretty similar to the dress-up that was in his Halloween group (which had a witch hat and also a needle in its tail (which is maybe why the tail looks infected almost?))
- Makes me think of a Halloween costume and you usually go out trick or treating at nighttime (which is why it thrives in the dark?)
My only issue is, I'm not sure it includes all the colours in the colour palette (unless I'm just blind) so I'm also thinking Oddity's isn't fully grown yet and that when it grows up it will have two heads similar to
a tattoo he has and also
this scene.
So in the case that it's not the witch cat, I gotta agree with @codexia on it being the ice-cream cat cause maybe the ice cream part will form another head when it grows? Also the kitty has a "tattoo"(?) on its left paw
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Then, like I said earlier, I think Wobbuffet is likely to be the ice cream cat but could also very well be the witch cat.
Wobbuffet doesn't have too many clues other than "My 2022 GH litter outcome has something in common with my 2021 GH litter outcome." which is pretty broad.
Either the cat is magic (the witch cat) OR (a big stretch here but hear me out) is related to Pee Wee's Big Adventure (which is what the 2021 outcome was inspired by). I've never watched Pee Wee in my life but when I looked up Pee Wee's Big Adventure and ice cream, I found out that it is actually a thing (ice cream soup) which could reference ice cream cat.

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My last guess is that this one is Squishy's

Usually Squishy's GH cats are a different species (This looks like a type of big cat but I'm not sure which one (maybe a cougar?)), has major lineart changes like this one, and also have slitted eyes.
And I think their hint regarding looking at their gallery is that their artwork always has a heart hidden in it? Their previous GH litters also have hearts on them and I think there is a sideways heart on this cat's left foot? Right at the bottom?
This was the only cat that I could find a heart on but maybe I'm just blind or maybe that wasn't the clue at all.