When you remove an insurance from a subscriber, it should remove it from the all covered dependents as well. It makes no sense because if you update/change the coverage it auto updates other family members, but when you remove it, it leaves it on every one else covered under the cancelled/terminated policy.
I cannot tell you how many times I've removed an insurance from the subscriber, got busy, and forgot to take it off the other family members. It should automatically do this , because they can no longer have the coverage.