The definition by the IRS for tax purposes is found in IRS
Publication 17:
"Permanently and totally disabled.
Your child is permanently and totally disabled if both of the
following apply.
·
He or she 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."
The doctor’s determination needs to be written, in case you ever
need to provide it to the IRS.
