answered:
Stitches, in raw power, is under Discord. But she doesn’t have an interest in raw power, so even if she possessed an absurd amount of chaos, she wouldn’t be using it the same way her brother does.
Scraps and Stitches both come from the same source. The golden apple of Discord. So they ended up inheriting the different aspects of chaos. On one hand, small chaos and clutter. Organized chaos. And the other, absolute, unbridled anarchy. Both have a bit of both, but you get the idea.