Yes, you can file jointly with her on-line for 2018.
You need to use $0 as her AGI because the IRS does not have a 2017 return on file for her.
You will need to prepare her 2017 tax return in with a TurboTax CD/Download product, print and mail the tax return. The IRS is no longer accepting 2017 tax returns via e-file.
For product information, follow this link: Past
Years Products
And congratulations!
