My child has always had a disability and I've never checked the dependent question box for "was disabled". Is it too late to start now?

[DawnC0]

You should check that box only if your child was permanently and totally disabled.  The definition of "permanently and totally disabled" for tax purposes is strict.

First, a doctor MUST certify that your condition has lasted, or is expected to last, for a year or more, or your condition is expected to lead to your death. Get the certification in writing and keep it with your permanent paperwork.

Second, you must be unable to "engage in any substantial gainful activity" because you are mentally or physically unable to do so. Your doctor will usually tell you what activities you can handle during your disability.

Here is a link to IRS Publication 524, Credit for the Elderly or Disabled, for more information about permanent and total disability.

https://www.irs.gov/pub/irs-pdf/p524.pdf

If you child meets the guidelines, then no, it is not too late to start making that selection.

[yengl88]

My child is 11 years old with a disability. He has been diagnosed with developmental delayed since he was 4-5 months, and has had it since and will most likely have it for the rest of his life. Do I need to send this certification writing from the doctor with my taxes?

[DawnC0]

No, you do not.  Keep it with your tax records.

[yengl88]

Because he's always had it since he was only 4 or 5 months old, how far back am I able to amend my returns for the previous years to catch my deductions for my child?