Final answer:
When the youngest child reaches age 16, the widow's/widower's blackout period begins and continues until the surviving non-remarried spouse reaches age 60, after which they may become eligible for reduced survivor benefits.
Step-by-step explanation:
Regarding Social Security survivor benefits, when the youngest child reaches age 16, the widow's/widower's blackout period begins and continues until the surviving (non-remarried) spouse reaches age 60.
This blackout period refers to the time during which the survivor benefits are not payable to the widow or widower because they are no longer caring for a child who is under 16. Once the surviving spouse reaches the age of 60, they may be eligible to receive reduced survivor benefits, and at age 65, they can receive full benefits.