The definition of a dependent child was redefined by the PPACA. For health insurance plans (encompassing dental and vision plans that are part of a single plan), a dependent is usually any child up to age 26. The marital, employment or student status of the child does not affect their status as a dependent child. However, if a dependent child has coverage available to him or her under another employer’s health plan, a grandfathered plan can omit that dependent from coverage, until the plan year renewing on or after Jan 1, 2014 which is when the new definition of dependent child must be incorporated into all Plans.