If born in 2019 and you did not claim them as dependents then you should amend 2019 and claim them. A child born anytime in 2019 is deemed to have lived with you the entire year so yiu will probably get a refund.
For the stimulus, just file a 2020 tax return since the stimulus was actually a 2020 stimulus. TurboTax for 2020 will as if you received the stimulus or not and if not it will go on the tax return.
Online for 2018 ended on Oct 15, 2019. 2018 and earlier can only be amended with TurboTax using the CD/download version installed on a PC or Mac computer.
2019 amended Federal returns can either be e-filed or mailed. 2018 and earlier amended returns can only be mailed. It is suggested that it be mailed certified with return receipt (or other tracking service) to verify that the IRS or state receives it.
See this TurboTax FAQ for detailed amend instructions:
https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed
-- Amended returns can only be mailed - allow 8-12 weeks - can take up to 16 weeks (4 months) for processing.
You can check the status of the amended return here, but allow 3 weeks after mailing.
https://www.irs.gov/filing/wheres-my-amended-return
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
