What is an essential person for ssi?

It is not clear what is meant by "ssi." If you are referring to Supplemental Security Income (SSI), a federal program that provides financial assistance to individuals who are disabled, blind, or aged 65 or older with limited income and resources, then an essential person for SSI may be someone who helps the recipient manage their finances or their daily living activities. This person may be a representative payee appointed by the Social Security Administration to receive and manage SSI payments on behalf of the recipient, or a caregiver who helps the recipient with tasks such as bathing, cooking, and medication management. The essential person for SSI may be a family member, friend, or professional caregiver.