Representative Payee for Auxiliary Benefits?

My husband is receiving SS retirement benefits and has an appointment in a few weeks to apply for auxiliary payments for our infant son. He was informed that he had to set up an account for a representative payee for our son’s checks to go into before benefits would be issued.

Everything that we look into seems to reference SSI, and we don’t have an award letter yet obviously for the auxiliary payment. Has anyone been through this process and knows how we would likely need to title such an account or if it’s another account entirely that we would need?

Thanks.