Emmy Rossum (b. 1986) is an actress and classically-trained singer performing since the age of three. She appears in a Word of the Day segment for season 45 of Sesame Street, presenting the word "focus" with Abby Cadabby. Photos and videos of her day on the set (seen below) were posted to Instagram.
Rossum played a young Audrey Hepburn in a 2000 TV movie for ABC, appeared in The Day After Tomorrow (with Dennis Quaid), the 2004 film adaptation of The Phantom of the Opera, the 2006 Poseidon remake, and plays the main character on Showtime's Shameless (with William H. Macy and Joan Cusack).