Do we consider our 23 yr old son a family member on FAFSA if we don't claim as exemption on return?

[4kidsdad]

he wanted to claim himself on his tax return so we don’t claim him as an exemption even though we could

If you could claim your dependent child, but choose not to; your dependent child can not claim his exemption, it is lost. See http://www.irs.gov/publications/p501/ar02.html#en_US_2014_publink1000220858

Dependent not allowed a personal exemption. If you can claim an exemption for your dependent, the dependent cannot claim his or her own personal exemption on his or her own tax return. This is true even if you do not claim the dependent’s exemption on your return. It is also true if the dependent’s exemption on your return is reduced or eliminated under the phaseout rule described under Phaseout of Exemptions, later.