5 CFR §843.406

1. (a)A child is considered to have been dependent on the deceased employee or retiree if he or she is—
   1. (1)A legitimate child; or
   2. (2)An adopted child; or
   3. (3)A stepchild or recognized natural child who lived with the employee or retiree in a regular parent-child relationship at the time of the employee's or retirees death; or
   4. (4)A recognized natural child for whom a judicial determination of support was obtained; or
   5. (5)A recognized natural child to whose support the employee or retiree made regular and substantial contributions.
2. (b)The following are examples of proofs of regular and substantial support. More than one of the following proofs may be required to show support of a natural child who did not live with the employee or retiree in a regular parent-child relationship and for whom a judicial determination of support was not obtained.
   1. (1)Evidence of eligibility as a dependent child for benefits under other State or Federal programs;
   2. (2)Proof of inclusion of the child as a dependent on the decedent's income tax returns for the years immediately before the employee's or retiree's death;
   3. (3)Cancelled checks, money orders, or receipts for periodic payments received from the employee or retiree for or on behalf of the child;
   4. (4)Evidence of goods or services that show regular contributions of considerable value;
   5. (5)Proof of coverage of the child as a family member under the employee's or retiree's Federal Employees Health Benefits enrollment; and
   6. (6)Other proof of a similar nature that OPM may find to be sufficient to demonstrate support or parentage.
3. (c)Survivor benefits may be denied—
   1. (1)If evidence shows that the deceased employee or retiree did not recognize the claimant as his or her own despite a willingness to support the child; or
   2. (2)If evidence casts doubt upon the parentage of the claimant, despite the deceased employee's or retiree's recognition and support of the child.