for this to be possible your mother would have to provide over 1/2 of your support while you provide over 1/2 the support for your child. this seems highly unlikely. there are also other tests.
here are the tests for QC and QR - 2021 tax year
You could be claimed as a qualifying child if all these tests are met
• You have the same principal abode as your mother for more than ½ the year. Temporary absences like for school are ignored
• If not a full-time student, you’re under 19 at the end of the tax year. If a full-time student, you're under 24 at end of the year
• you haven't provided over ½ your own support
• you didn't file a joint return unless there was no tax liability but merely filing jointly to facilitate refund of taxes withheld or estimates paid
Or as you could be a qualifying relative if all these tests are met
You’re related to the other person or, if not, lived with the other party for the entire year and
• your gross income for 2021 is less than $4,350
• your mother provided over ½ your support
• you aren't a qualifying child of another taxpayer
