Dependents can not be claimed by two taxpayers. You will have to resolve the issue and if you decide you can not claim the dependents then you will have to file an amended return.
Your mother would most likely have priority to claim the dependents as she would be the biological parent.
If you feel that you should be able to claim the dependent, you’ll need to print and mail your return. You won’t be able to e-file. The IRS won’t allow two different people to e-file using the same dependent Social Security number (SSN).
The IRS will then send a letter to both of you to determine who gets to claim the exemption for the child. If you can’t agree on who claims the child, the tie-breaker rules apply. Under the tie-breaker rules, the child is a qualifying child only for:
- Whoever the child lived with the longest during the tax year
- The parent with the highest AGI if the child lived with each parent for the same amount of time during the year
- The person with the highest AGI if no parent can claim the child as a qualifying child
- A person with an AGI higher than any parent if the parent can claim the child as a qualifying child but doesn’t
If the other taxpayer is uncooperative, the IRS will eventually contact both of you to figure out who gets to claim the dependent. The losing party will then be liable for any additional taxes, penalties, and/or interest as a result of the false claim.
