Q. Would SSDI be considered earned income?
A. No
For a disabled (or fulltime student) spouse the IRS allows you to enter a fixed number ($3000 for a full year).
From the form 2441 instructions:
For each month or part of a month your spouse was a
student or was disabled, he or she is considered to have
worked and earned income. His or her earned income for
each month is considered to be at least $250 ($500 if you
had two or more qualifying persons at any time during
2021). Enter that amount on line 5. If your spouse also
worked during that month, use the higher of $250 (or
$500) or his or her actual earned income for that month.
