Is SSI benefits taxable?

There are two types of payments:

• A portion of SSDI (Social Security Disability Income) may be taxable. You should receive a Form 1099-SSA from Social Security which can be entered directly into TurboTax. If SSDI is your only income you would not be required to file a return.
• SSI (Supplemental Security Income) is non-taxable. From Publication 970:  "Social security benefits do not include SSI payments, which are not taxable. Do not include these payments in your income."   Because they are non-taxable, any legal fees to secure the benefits are not deductible.

(Also, if the SSDI payments are to children and the Form 1099-SSA is in the child's name they would be reported on the child's return, not the parents.)

I added it my tax return. Shouldn't I not included it. Please kindly let me know.