Trachtenberg's death shocked fans and saddened co-stars, who remembered the child star-turned-teen show favorite as big-hearted and hard-working in social media tributes following her death. While her rise to fame was fueled in part by television appearances,

Celebrities excluded from the Oscars In Memoriam tribute is causing a stir online. On Sunday, Morgan Freeman presented the segment at the Academy Awards, which honored actors and filmmakers who died over the last year including Gene Hackman, James Earl Jones, David Lynch and Maggie Smith.

The decision about which stars are included -- or excluded -- from the tribute at the Oscars comes down to time.