Final answer:
Formal documentation of a family care plan is not required for single members with no dependents, whereas it is essential for members during deployments and when stationed overseas.
Step-by-step explanation:
Formal documentation of a member's family care plan is not required under the circumstance where the member is a single member with no dependents. In situations such as during deployments and when stationed overseas, it is essential for military personnel to have a family care plan to ensure their family members are taken care of in their absence. However, for single members who do not have dependents, this requirement would not apply as they do not have the same responsibilities for caring for others. This consideration helps to relieve some of the stress and ensure smooth operations when military personnel are away from their families.