Evidence of a child's dependency on the employee is required when -
(a) The employee is receiving an annuity that can be increased under the social security overall minimum (see part 229 of this chapter) by including a child, grandchild or a spouse who has a child in his or her care;
(b) A wife under age 65 applies for a full spouse annuity because she has a child or a grandchild of the employee in her care; or
(c) A child or someone in behalf of a child applies for a child's annuity based on the deceased employee's record.