Paging Marlee Matlin?
Sources confirm to E! News that CSI producers are seeking an actress to play the mother of Gil Grissom. Casting notes describe this woman as a "strong, confident, intelligent and influential woman [who] has never allowed her lack of hearing to keep her from doing anything she wanted, and has no trouble making her feelings known to one and all."
Indeed, the character is deaf. She's also a former librarian that is fluent in American Sign Language.
Look for Gil's mom to show up on episode 13 of this season, titled "The Two Mrs. Grissoms." The first Mrs. Grissom, of course? That would be Sarah Sidle.