You need to delete the dependent off your tax return.  Even if you indicated that ''the other parent is claiming this dependent'', the child is most likely still there.  

Click on MY INFO on the left side menu and scroll down to where the dependents are listed.  Use the trash can icon or delete button to remove any dependent(s) that you are not claiming.  If you need to remove the Dependent Care Credit, use this link.   How do I delete Form 2441 in TurboTax Online? 

No, this is my year to claim the child as a dependent, but as her mother is the custodial parent she gets to claim the child for the Child and Dependent Care Credit. I have a second child, from my current marriage, that I get to claim this credit for, but Turbo Tax keeps automatically adding the first child to get my a higher deduction. This is wrong, my return was rejected for this reason.

Did you get a form 8332 from the mother?  If the mother already claimed her, you will have to file by mail.

Yes I did receive the 8332. This was not a tax issue, it was a technical issue with the Turbo Tax System. Tech Support helped and got it taken care of.

Great; I am glad to hear that you got it worked out!