Otherwise the IRS may apply it in any manner they want. Every payment should include your name, your taxpayer identification number, the type of tax you are paying, and the period the tax payment is for. Make sure the name and social security number on your tax return agree with the Social Security Administration's records. If you change your surname, notify the Social Security Administration and request a new social security card. Don't claim a tax exemption for your child unless you are entitled to do so.
Special rules apply to divorced parents.
If both parents claim the child as a dependent, both returns will be subject to further IRS review. Respond promptly to any notice you receive from the IRS, even if you think the notice is incorrect. If the IRS doesn't hear from you within the time specified on their notice, you may lose the right to protest any changes made to your return. If you fail to provide the IRS with your current mailing address, you may not receive a refund check or a notice if there are problems or adjustments to your return. And even if the IRS can't find you, penalties and interest will continue to accumulate on any tax due.