Someone improperly claimed my then-18-year-old adopted sister as a dependent on their 2018 taxes. She lived there for 1 month. Can this be fixed and is it worth it?

[malandseadel]

My sister was adopted by our parents from foster care at a young age. When she turned 18, she reconnected with bio-parents and moved in with the bio-mom for 1 month. Quickly, she realized fantasy wasn't reality. The bio-mom claimed her on their 2018 taxes, claimed my sister's return was $600, and refused to give it to her.  My sister has continued to struggle with rebellion, returning to live with our adopted parents, and starting her own life.  She's almost 21 now and with talk of the stimulus check, wanted to be sure her bio-mom wasn't going to get more of her money she didn't deserve.  I don't know how to advise her.  Is it worth it for her to try to file her previous year (2018) taxes and perhaps cause an audit?  Will her bio-mom get stimulus money that should be hers? Does she have any recourse?

[Anonymous]

an adopted child is treated as a child by blood

thus your sister would qualify as your mom's qualifying child if all these test are met

•  she have the same principal abode as mom for more than ½ the tax year.  Temporary absences like for school are ignored
• she be under 19   as of 12/31/2018
• mom has provided over ½ her support
• no joint return unless no tax liability but merely filing joint to facilitate refund of taxes withheld or estimates paid

can say how much tax benefit mom would get if she amended .18 to claim your sister

any dependent  older than 17 is not a qualifying dependent for the stimulus check.