Social Security Disability is designed for people who are unable to WORK due to a long-lasting or permanent medical condition that may render him/her unable to secure gainful employment. A 93 year-old person is not in the job market any more. SS Disability doesn't' apply.
She's not referring to SSDI, she's referring to SSI which is Supplemental Security Income. That program is available to those who even with SS or SSDI make under a certain amount, as vegas lady said, $841. So if the 93 year old's SS income is less than $841 it may be worthwhile to look into.
The maximum payment for SSI in 2022 is $841 per month. If her current income is above that don't bother applying for SSI. It is Supplemental Security Income and it doesn't supplement if the income is already above that. An Aged, Blind or Disabled person might qualify if they are impoverished (low income and assets) but being 93 and then also becoming blind does not increase the eligibility for SSI or the payment. If she might eligible call the Social Security Administration at 1 800 772 1213 to apply.
you need to bring her to your nearest social security office with all of her required personal documents, ( birth certificate, 2 forms of ID,mail that shows her address, social security card) and see if she qualifies.
https://www.ssa.gov/benefits/ssi/