Can I get 3rd stimulus money for new dependent when ex claimed him last year

[mist594016]

My ex-mother-in-law had my 16 year old last year for 7 months and claimed him on her 2020 taxes but he moved in with me in August 2020. I want to know how I  can get the 3rd stimulus and on for him. We really need the money right now I don’t wanna have to wait till the 2021 tax season

[NCperson]

unfortunately, it doesn't work that way.

the 3rd stimulus is an advance credit against the 2021 tax return.  The only way to get the $1400 is 

1) wait on the stimulus payment from the IRS.  You can't apply for it.

2) Obtain the Recovery Credit on the 2021 tax return.

[Hal_Al]

For more, see this discussion:

https://ttlc.intuit.com/community/tax-credits-deductions/discussion/3rd-stimulus-dependent-eligibili...