"We've seen so many parents struggle, and it's heartbreaking," Ms Roesler said.
"I'm not bagging the schools; they do some great work.
"But their hands are tied, the money isn't there, and I feel stumped about what to do next."
Ms Roesler said her son, who has high-functioning autism, had to be taken out of school for his safety, as a teacher felt unable to differentiate their style to accommodate him.
"After that, he had made a plan to kill himself," she said.
"He was asking what I'd do, and what the school would do, if they found him.
"His sister went absolutely white when she clicked -- it was devastating."
Ms Roesler's son is actually one of the luckier ones -- after "a long battle", she was able to secure him Ongoing Resource Scheme (ORS) funding.
But many of the parents she supports feel unable to push for resources as they have been belittled and ignored by school staff.
"Many autism parents don't speak up, because they've been burnt.
"They've been ridiculed and rejected -- because their kid looks normal, they've been told they're paranoid and are making it all up."
Ms Paterson said parents were also seeing their children excluded from school life.
"Parents are getting phone calls saying their kids can't come on school trips because they won't be able to supervise him.
"It's not okay -- our kids have a right to education.
"Schools say they have a policy of inclusion, but that's not happening."
Ms Roesler will be meeting with the Ministry of Education to discuss her son's situation -- but asks for a shift in attitude towards the parents who feel unable to put up a fight.
"As a community, we can do more to support these parents.
"They are so resilient -- they should be wearing their undies over their clothes because they are superheroes.
"But, if their kids don't get support, there'll be some tragic endings."