Katie Cassidy revealed the actor's final words on Twitter Friday. Katie Cassidy and David Cassidy arrive at the 9th annual Family Television Awards held at the Beverly Hilton Hotel, Nov. 28, 2007 ...

Singer, actor David Cassidy poses for a portrait in Minneapolis, Minn. on July 1, 1990. Jim Steinfeldt/Michael Ochs Archives/Getty Images Cassidy, who lived in the Fort Lauderdale area ...

David Cassidy from Season 2 of 'The Partridge Family' in 1971. Credit: ABC via Getty Images David Cassidy, who became famous in the 1970s playing Keith Partridge on The Partridge Family ...

An audience of young pop fans at a David Cassidy concert at White City Stadium, west London. (Photo by Evening Standard/Getty Images) The single “I Think I Love You,” featuring Cassidy on lead ...