Can I back up and withdraw the question about supporting my daughter? I only make her car payments, but now my return process is stalled because I don't have her ssn.

It sounds like you would like to delete your daughter from your return. Here's how to remove her: 

1. Sign into your TurboTax Deluxe online account.
2. Select "Take me to my return"
3. Beside your daughter click on the trash can to delete her information (see attachment)