How can I get others to understand my child's disability traits, rather than thinking "it can't be helped because of the disability"?

To avoid it ending at "it can't be helped," it's effective to convey, as a set: (1) the behavior that's troubling, (2) its background (the traits), (3) what you're doing at home and preschool, and (4) what you'd like those around to do. Showing "it's not willfulness—there's this reason, and here's how we respond" leads to understanding that is neither resignation nor indulgence. Summarizing it in a support book makes it easier to convey across a change of teacher or a new setting. Rather than trying to get everything understood at once, focusing on key points by person and situation gets through better.