A spouse and unmarried children under 21 may qualify for TD, but TD depends on the principal, so an unresolved admissibility issue affects them too. Each family member also has their own history and their own admissibility, and a dependent's prior overstay is a separate review.
Review each person separately
Ask counsel to look at every family member's record, not only the principal's, and keep in mind that TD permits study but does not authorise work of any kind. A child who is a United States citizen does not need TD. Where a dependent has a history issue of their own, address it in the same confidential review rather than discovering it at an appointment.
A spouse holding TD can study but cannot rely on that status for employment to offset a difficult rotation schedule. Accompanying TD status does not authorize employment, including a job mentioned in the principal’s employer material. Include every TD dependent in the status review: the job ending does not necessarily mean immediate loss of status because the grace-period provision also covers dependents. Families often act on a start date by giving notice on a lease, enrolling a child, or ending a spouse's employment.