As a semi-pro photographer, one of the rules we adhere to (I think on police advice) is not to film children without parental consent.
My good lady wife works in Childcare and Rule #1 of Safeguarding is 'You cannot take/publish images of children without parental consent'. I recently attended a Safeguarding 'course' where one example given involved the image of a 'protected' child taken on an outing by another parent being published on social media. As a result, a parent of said child, who did not have visiting rights, tracked said child down through the published image.
None of that is law. Whilst in public you can take pictures of whatever the hell you like.
Now, in general cases, yes it is advisable to get parental consent, but it is not required.
And if the kids are acting like little toerags (like the ones in this case are) then sorry but any good will I may have to them goes out the window.
What you say definitely applies to *adults*, not sure about children.
It applies to everyone and everything.
Sometimes it is too easy to use the "disability card" - starting to believe there is no smoke without fire !
You messed up your quote, but I am assuming this is what you wrote.
In which case, the kids and mother where specifically abusing her based on her disability.
I fail to see how that is "using the disability card".