In rare cases, neither of a child's parents claim him or her as a dependent. If this occurs, questions might arise about who can receive qualifying child tax benefits. The IRS has specific rules regarding this situation. 

If an individual's parents may claim the individual as a qualifying child but no parent does so, no other taxpayer may claim the individual as a qualifying child unless that taxpayer's adjusted gross income (AGI) is higher than the highest AGI of any parent of the individual. (Code Sec. 152(c)(4)(C))