Yes, if you meet all the qualifications below. He would have to say that he is being claimed as a dependent. If he already filed and did not declare this, he will have to amend his return and you will have to mail yours in.
In general, to be a taxpayer’s
qualifying child, a person must satisfy four tests:
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.
