SSI pays benefits to people who are (a) disabled and (b) have minimal or no assets/resources.

An SSI recipient does not have to have ever worked or paid into the SSA system.

Children (under 18) who are disabled can qualify for SSI benefits as well.

An SSI recipient’s spouse and/or children do not qualify for additional SSI benefits.

Find more information here: https://www.ssa.gov/ssi/text-eligibility-ussi.htm