My son enlisted in the Marines after high school and is stationed overseas. Can I claim him as my dependent?

Probably not. Once a child is 19 years or older and not a full-time student, then he/she is not a dependent unless gross income is below the exemption amount ($3,950 for 2014; $4,000 for 2015) and other tests are met. A dependency exemption can be claimed if the child is under age 19 by year end and does not provide more than half of his/her support for the year (regardless of the child’s gross income); military service is viewed as a temporary absence from the home.