you do have the option if you could claim your child either as a qualifying child or qualifying relative of not doing so by amending your return. however, if you could claim the child the child must file an amended return indicating (s)he could be claimed as a dependent on another's return. returns are filed under penalty of perjury and that's what the child did if (s)he falsely claimed they weren't someone else's dependent.
here are the tests to determine if you could claim the child
you can claim as a qualifying child if all these tests are met
• child has the same principal abode as you for more than ½ the tax year. Temporary absences like for school are ignored
• if the child is not a full-time student, they are under 19 at the end of the tax year. If a full-time student, they are under 24 at the end of the tax year.
• child hasn't provided over ½ their own support
• child didn't file a joint return unless there was no tax liability but merely filed jointly to facilitate refund of taxes withheld or estimates paid
or you can claim as a qualifying relative if all these tests are met
• child's gross income for 2020 less than $4,300
• you provided over ½ child's support
• child isn't a qualifying child of another taxpayer
you can no longer amend using your iPhone or even online.
you would need a desktop version for a full desktop computer either a MAC or WINDOWS
the return can not be e-filed.
