Yes, but only if your son amends and says that he is being claimed and removes his child from his own return. Please see the asterisk below. I am assuming the wife also made no money. Your grandchild could be a Qualifying Child if he lived with you. You would have to mail in your return.
Qualifying Child
Relationship — the taxpayer’s child or stepchild (whether by blood or adoption), foster child, sibling or step-sibling, or a descendant of one of these.
Residence — has the same principal residence as the taxpayer for more than half the tax year. Exceptions apply, in certain cases, for children of divorced or separated parents, kidnapped children, temporary absences, and for children who were born or died during the year.
Age — must be under the age of 19 at the end of the tax year, or under the age of 24 if a full-time student for at least five months of the year, or be permanently and totally disabled at any time during the year.
Support — did not provide more than one-half of his/her own support for the year.
*Marital status — if married, did not file a joint return for that year, unless the return is filed only as a claim for refund and no tax liability would exist for either spouse if they had filed separate returns.
