A waiver may be available for an alien who has been convicted of, or admits having committed, or admits committing acts which constitute the essential elements of a violation of (or a conspiracy or attempt to violate) any law or regulation of a State, the U.S., or a foreign country relating to a controlled substance (as defined in section 102 of the Controlled Substances Act (21 U.S.C. 802)).
To see if your foreign family member qualifies, contact an immigration attorney at 626-771-1078.