5 C.F.R. § 843.405 Dependency.
Title 5 - Administrative Personnel
To be eligible for survivor annuity benefits, a child must have been dependent on the employee or retiree at the time of the employee's or retiree's death.
Title 5: Administrative Personnel
PART 843—FEDERAL EMPLOYEES RETIREMENT SYSTEM—DEATH BENEFITS AND EMPLOYEE REFUNDS
Subpart D—Child Annuities
§ 843.405 Dependency.