Taxpayers can claim a child tax credit for each qualifying child.How is a qualifying child defined?

A qualifying child is a son or daughter or descendant of either,a stepson or stepdaughter or descendant of either,or a foster child who the taxpayer can claim as a dependent.The qualifying child must also be a U.S.citizen or resident who is under the age of 17 at the end of the tax year,be younger than the person claiming the credit for the child,and be unmarried.