Can I write off my dependent care expenses if the person who was watching my child is over 19, not my dependent but was filed as some else's dependent?

No it does not matter for you that the childcare provider can be claimed as someone else's dependent.  They just cannot be YOUR dependent.

Yes, a dependent can have a job.   The childcare provider is responsible for reporting their own income on a tax return.  You do not have to concern yourself with their tax return.  What you need is the childcare provider's Social Security number or Tax ID.

Yes, you can still claim the dependent care expenses if the childcare provided is a dependent on another individual's return.  As xmasbaby0 stated, a dependent can have a job without paying for more than half of their support.  

To claim dependent care in TurboTax, follow these steps:

1. Click Deductions and Credits
2. Scroll down to you and your family
3. Click Revisit/Start next to dependent care credit
4. Follow the interview questions to enter the dependent care expense

For more information on dependent care deductions, see the link below:

Child and Dependent Care Tax Credit

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