If he meets the tests to be claimed by you, you can claim him as your dependent. You do not enter his income on your tax return.
If he had less than $6300 of W-2 income, he does not need to file a tax return. However, if he had federal income tax withheld, he should file a return to get a refund.
If his income was reported on a 1099-MISC or not form, he must file a return if it was more than $400.
If he files a return, he needs to indicate that he can be claimed by someone else.
Here are the tests to determine whether you can claim him or not:
1. The child must be your son, daughter, stepchild, foster chld, brother, sister, half brother, half sister, stepbrother, stepsister, or a descendant of any of them.
2. The child must be (a) under age 19 at the end of the year, (b) under age 24 at the end of the year and a full-time student, or (c) any age and permanently and totally disabled.
3. The child must have lived with you for more than half of the year. Temporary absences while away at college are considered living with you.
4. The child must not have provided more than half of his or her own support for the year.
5. If the child meets the rules to be a qualifying child of more than one person, you must be the person entitled to claim the child as a qualifying child.
6. The child must be a U.S. citizen or U.S., Canada or Mexico resident for some portion of the year.
7. The child must be younger than you (or your spouse, if filing jointly) unless disabled.