Which scenario does not qualify as a qualifying child for the Earned Income Tax Credit?

In order to qualify as a qualifying child for the Earned Income Tax Credit (EITC), certain criteria must be met, including the requirement that the child must have lived with the taxpayer for more than half of the tax year. The scenario where a child lived with the taxpayer for only 4 months does not fulfill this requirement, as it clearly falls short of the necessary timeframe of over 6 months. Thus, this situation does not qualify the child for the EITC.

In contrast, the other scenarios potentially meet the qualifying criteria. A younger sister can be a qualifying child as long as she meets the age and residency requirements set forth by the IRS. A full-time student aged 22 could also qualify; despite being over 19, full-time students can still be eligible up to the age of 23, provided other conditions are met. Lastly, a married son who is 18 years old could still be considered a qualifying child if he lives with the taxpayer and meets the other relationship and age criteria. Each of these scenarios presents conditions that could qualify for the EITC, unlike the situation involving the child who lived with the taxpayer for only 4 months.