If you have had the challenges of finding, placing, and paying for educating and/or treating one of your children for his/her special needs, you know that this process is not something you wanted or chose. As such, you DO want to tell the financial aid office(s) at the college(s) of any of your other children.
Financial aid calculations strive to equitably allocate federal, state and institutional aid based on income and assets, but you can appeal based on certain non-discretionary expenses. Track and report all associated medical and dental expenses in excess of 4% of your income, (report on schedule A of the 1040); your tax professional can advise as to which expenses may here qualify.
Additionally, document and provide the costs at residential, day or other education/treatment institutions. The Profile, (the College Board's form for many private institutions) does ask about private secondary tuition, but a college may choose whether or not to take that into consideration. I have not known of a school not taking special needs' costs into consideration to reduce available income for the calculations.
If the Profile is not required by your child's school, write an appeal letter with documentation, (assessment, diagnosis, and costs), and send to your child's financial aid counselor. DO NOT go directly to the Financial Aid Director, as this usually slows the process.
If you have any questions, feel welcome to contact me directly. We have built out a virtual financial aid consulting center, where I have just gone live fielding questions on-line for free.