Provides new, targeted federal funding through the Social Services Block Grant (SSBG) to pay for diapers, diapering supplies, medically necessary diapers, and adult incontinence materials for people in need, and requires State and eligible local grantees to use, report, and evaluate those funds under HHS guidance. Also adds "medically necessary diapers" and "diapering supplies" to the list of qualified medical expenses reimbursable from HSAs, Archer MSAs, health FSAs, and HRAs, with the tax-account changes taking effect in late 2025.