Have to claim exemption for child to file HOH?

Do not have any information regarding SSN/ITIN but Publication 501 mentions claiming someone as an exemption if filing HH based on being considered unmarried.

Considered Unmarried

To qualify for head of household status, you must be either unmarried or considered unmarried on the last day of the year. You are considered unmarried on the last day of the tax year if you meet all the following tests.

You file a separate return. A separate return includes a return claiming married filing separately, single, or head of household filing status.

You paid more than half the cost of keeping up your home for the tax year.

Your spouse did not live in your home during the last 6 months of the tax year. Your spouse is considered to live in your home even if he or she is temporarily absent due to special circumstances. See Temporary absences , later.

Your home was the main home of your child, stepchild, or foster child for more than half the year. (See Home of qualifying person , later, for rules applying to a child's birth, death, or temporary absence during the year.)

You must be able to claim an exemption for the child. However, you meet this test if you cannot claim the exemption only because the noncustodial parent can claim the child using the rules described later in Children of divorced or separated parents (or parents who live apart) under Qualifying Child or in Support Test for Children of Divorced or Separated Parents (or Parents Who Live Apart) under Qualifying Relative. The general rules for claiming an exemption for a dependent are explained later under Exemptions for Dependents .

If you were considered married for part of the year and lived in a community property state (listed earlier under Married Filing Separately), special rules may apply in determining your income and expenses. See Publication 555 for more information. Nonresident alien spouse. You are considered unmarried for head of household purposes if your spouse was a nonresident alien at any time during the year and you do not choose to treat your nonresident spouse as a resident alien. However, your spouse is not a qualifying person for head of household purposes. You must have another qualifying person and meet the other tests to be eligible to file as a head of household. Choice to treat spouse as resident. You are considered married if you choose to treat your spouse as a resident alien. See chapter 1 of Publication 519.

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