W. Va. Code § 21-5D-5 – Certification.

(a) If an employee requests family leave to care for a family member with a serious health condition as authorized in this article, the employer may require the employee to provide certification by a health care provider of the health condition.
(b) The certification shall be sufficient if it contains the following:
1. (1) That the child, dependent, parent or employee has a serious health condition;
2. (2) The date the serious health condition commenced and its probable duration; and
3. (3) The medical facts regarding the serious health condition.