Are there any sources of income that are not counted towards your SSI claim (i.e., VA Disability, Child Support)?
Yes, there are a number of unearned income (e.g. income derived from a source other than working) exclusions in the SSI program. There is a comprehensive list here, with links to more information about each source: https://secure.ssa.gov/poms.nsf/lnx/0500830099.
VA Disability payments are not excluded when looking at countable income for the SSI program, and you’ll see that they aren’t included in this table. These benefits are counted dollar for dollar, after a general exclusion of $20. For Veterans who receive a VA Disability Pension and are applying for SSI, their income will almost certainly be too high from the Pension payment to qualify for SSI. That said, they paid into SSDI through their military service and may qualify for SSDI, so that is worth exploring (for that, check with SSA to see if the Veteran has enough work quarters to potentially qualify for SSDI).
Child support payments are in this exclusions table (though the regulations can be a bit hard to sift through) – basically, SSA will exclude one-third of support payments made on behalf of a child when determining countable income. I find this link easier to read when discussing child support and main exclusions: https://www.ssa.gov/OP_Home/cfr20/416/416-1124.htm.