No it won't affect you. But how old is he and is he a full time student? If he made over 4,700 you might not be able to claim him.
Be sure on their return they check the box that says they can be claimed on someone else’s return. If their only income is W2 and under 13,850 they do not have to file a return except to get back any withholding taken out.
Filing requirements for a dependent
https://ttlc.intuit.com/community/children-dependents/help/do-i-need-to-file-my-own-taxes-if-i-m-a-d...
