Joaquin Phoenix honored his late brother River Phoenix during his acceptance speech at the Academy Awards on Sunday night (Feb. 9).While accepting the best actor Oscar for his performance in Joker, Phoenix touched on a number of issues including cancel culture, animal activism, racism and gender equality before quoting a song lyric written by his brother, who passed away from a drug overdose outside Los Angeles' famed Viper Room in 1993 at the age of 23.