Can children under age 26 be covered as dependents on their parents' plan if they are eligible for their own coverage (e.g., at another job)?

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• My child is about to turn 26, what do I need to do to remove him or her from coverage?
• Can a dependent be dropped from coverage in the middle of the plan year?
• I have a child who is attending college out-of-state and under the age of 26. Is my child still eligible to be on my insurance coverage? Would my child be covered for out-of-state care?
• If two employees in the same plan (state, local education or local government) are married, are they required to choose the employee + spouse premium level, or can each sign up for employee only coverage? What if there are children?
• Can I cancel my insurance coverage for any reason and what documentation is required?