Does a dependent child's coverage under a parent's group benefits plan end immediately when the parent dies?

Not necessarily immediately, but it usually does end at some point, and exactly when depends on the specific group benefits plan rather than a general rule. Some plans provide a defined continuation period for dependents after the covered employee's death, giving the family some transition time, and may offer an option to convert to an individual policy before that period runs out. Other plans end dependent coverage on the date of death, or very shortly after, with no continuation built in at all.

Because this varies so much between employers and insurers, the family shouldn't assume coverage continues, or that it ends, without checking. The plan booklet, the employer's HR department, and the insurance carrier are the sources to go to for the actual answer, and doing so promptly matters if there's a conversion deadline that needs to be met.

If you're a parent with dependents relying on your workplace group benefits, it's worth finding out now what happens to their coverage if you die, so your family isn't scrambling to understand the plan's rules on top of everything else they're dealing with after a death.