When you prepare your 2020 return you will claim your child born in 2020 as a dependent. Enter your child's Social Security number and make sure the child is shown as a dependent at the top of your Form 1040. When it asks how long the child lived with you in 2020 say the whole year. That way you get the child--related credits your are eligible for and the stimulus money. Wait until late February so the dust settles on the stimulus money so you can get all of it on your tax return.
The stimulus check is an advance on a credit you can receive on your 2020 tax return. If something went wrong or you did not get the stimulus check this year, you can get it when you file your 2020 return in early 2021—if you are eligible.It will end up on line 30 of your 2020 Form 1040.
https://www.irs.gov/newsroom/economic-impact-payment-information-center-topic-j-reconciling-on-your-...
https://www.irs.gov/coronavirus/coronavirus-tax-relief-and-economic-impact-payments-for-individuals-...
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
