In certain circumstances, you do not need to claim the child as a dependent to qualify for head of household filing status, such as when the qualifying child is unmarried and is your child, grandchild, stepchild, or adopted child. Refer to Publication 501, Exemptions, Standard Deduction, and Filing Information, for more information.

References:

• Publication 501, Exemptions, Standard Deduction, and Filing Information

Source: www.irs.gov