Oscar-nominated Joaquin is known for preferring a life outside the limelight and keeping his private life away from the cameras, but on 30 September he joined his sisters and mother on the red carpet.
Joaquin, 40, looked smart in a suit as he smiled while stood with siblings Summer, Liberty and Rain, his mum Arlyn, and businessman Jeffrey Weisberg.
The family attended PETA's 35th anniversary gala to launch a new award named in River's honour. The River Phoenix Humanitarian Award recognizes the late actor's passion for animal rights and will celebrate those who have continued that work.
River was a PETA spokesperson and animal rights activist during his short life: he won PETA's Humanitarian of the Year Awards in 1992 and frequently campaigned for environmental causes.
He was 23 years old when he collapsed and died outside The Viper Room in LA in 1993 following a drug overdose. Joaquin and Rain were with him at the time and called for help but it was too late.
Jeffrey Weisberg is executive director of the River Phoenix Centre for Peacebuilding, which aims to enrich the lives of individuals, families and communities by providing and promoting the best practices and principles of peacebuilding and global sustainability.
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