Sylvester Stallone has revealed details of his past in new Netflix documentary, Sly, including memories of his abusive father.The documentary, which aired last week, shows Stallone delving into his childhood and rise to stardom, and features interviews with his co-stars including Quentin Tarantino and Arnold Schwarzenegger.Directed by Thom Zinney, the film features the Rocky star sharing intimate details of his experience growing up in New York and Maryland, including his challenging home life.The actor hinted that his violent father inspired some of his previous work, saying: “My father was Rambo, in reality”, referring to his portrayal of John Rambo in the 2008 movie, Rambo.He continued, “I was raised by a very physical father. Nothing was ever settled verbally.