Can you claim unemployed boyfriend and grandchild as dependents?

Maybe. If your boyfriend lived with you the entire year, and there is no local law against your cohabitation, and his income was less that $3,500 (in 2008), and you provided over half of his total support for the year, you may claim him as your dependent. If your grandchild lived with you over 1/2 the year, and was under age 19 on December 31, or under age 24 and a full-time student, or any age and permanently and totally disabled, and you provided over 1/2 of his or her support for the year, you may claim him as your dependent.