Tamblyn made her first appearance last month at the start of the show's 11th season.
She plays Jenny, the late Charlie Harper's "illegitimate daughter who moved to Los Angeles to pursue acting and to connect with what's left of her family," a synopsis said.
"Jenny's now living in Walden's beach house, along with her uncle Alan. She happens to like everything her dad liked -- including women."
Charlie Sheen played Charlie Harper for eight seasons. The character was killed off after Sheen was fired for his real-life drug use, erratic behavior and insubordination.