If my child is diagnosed as Level 2 Autistic, do I need to mark that this child "was disabled" on my taxes?

[DoninGA]

If the child is under the age of 13, indicating they are disabled does not get you any type of credit or deduction on a tax return.

Age 13 or older and disabled gives you the Child and Dependent Credit if you need someone to care for them while you work.

Age 19 or older to be disabled this is the IRS definition -

Permanently and totally disabled.

Your child is permanently and totally disabled if both of the following apply.
• Your child can't engage in any substantial gainful activity because of a physical or mental condition.
• A doctor determines the condition has lasted or can be expected to last continuously for at least a year or can lead to death.