If you and the other bio-parent live together with your child as a family, then only one of you should claim the child. The other parent files Single and does not enter anything about the child on their tax return.
In situations where the parents do not live together----whether they are divorced or never married---then the IRS cares which parent is the custodial parent. That is the parent who the child spends the most nights with---at least 183 nights in the year. The custodial parent may (or may not) sign a form 8332 that allows the non-custodial parent to claim the child for the child tax credit. But the custodial parent retains the right to file Head of Household, get earned income credit, and get the childcare credit.
**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.**
