
I don't get why people are so mad abt the kid being in this special ch. Like I know it can be a bit uncomfortable but he's older in it so....

You realize that distinction is arbitrary because the child in question isn't real, right? The only thing he "actually" is is a 2D rendering of the artist's imagination. Like genuinely, there is no difference in an author "modifying" a character to look grown and the character being grown because this is a comic. The story is told visually.
Case and point, the short was a draft for the story where M2 WAS grown. Plus, It so obviously is not canon, so no, I don't understand where this arbitrarily becomes difficult for people like you to cope with.

So you'd be fine with a time skip... But the short is an issue? I really can't
The only difference would be in one the age change is canon and in the other it isn't. It would still be just as abrupt, so what what magically makes one okay and not the other?
Like I said, this shirt was drawn likely before the story as we know it was. Even if it wasn't, the purpose of a short is to show something the reader usually wouldn't see in the main story. M2 is the only side character (as in a character without a main scene in the plot) that readers can put a face to their name. Besides maybe Big A, but with mystery regarding his disappearance and how selective the author's been with showing his face it's obvious a short about him would give away too much too soon.
Seriously, name a character that would've worked better.
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