Mel Brooks' son, Nicky Brooks, is sharing a lesser-known side of his famous father ahead of the director's monumental 100th birthday. "My dad tended to express anxiety, stress through anger, and he became a very angry person, very volatile mood-wise," Nicky recalls in the upcoming two-party documentary Mel Brooks: The 99 Year Old Man!, premiering January 22 on HBO, per Entertainment Weekly. "It was difficult for my mom trying to raise these babies, and I think it just reached a point where my dad was just frankly so difficult to live with," Nicky continues in the documentary. "It was just intolerable." The famed director shares Nicky, daughter Stefanie Brooks and son Eddie Brooks with his first wife, Florence Baum. He also shares Max Brooks, the author of World War Z, with his second wife, Anne Bancroft. Rob Reiner Recalls Dad Carl's Heartbreaking Death in Doc Before His Murder In the film, which includes interviews with some of Mel's famous collaborators including Judd Apatow and the late Rob Reiner, Nicky also recalled how much his father wanted to be famous. "My dad was very hungry for stardom; he really wanted desperately to be a somebody," Nicky tells the cameras. "Not just to be a kind of industry success in some abstract way, but to be recognized and noticed and appreciated." In his 20s, Mel enjoyed some mild success early in his career while writing for Your Show of Shows in the 1950s. When the show ended in 1954 after four seasons, Brooks reportedly went from making $5,000 per episode to "next to nothing," Entertainment Weekly adds. Mel Brooks Getty Images "That was real money, and then I wasn't working," the director tells Apatow in the film, going on to explain that losing that income meant he could no longer afford to see his therapist or continue to find support when it came to managing his anxiety. "I cried for two years," Mel reportedly says in archival interview footage used in the documentary. "For two years, I did nothing but sob. I mean, I was broke." The director's daughter, Stefanie, also opened up to the documentary cameras about her father and his relationship with her mother, Baum. "My father made my mother stop working, because she was his wife," she recalled. "It was a dynamic that was very common at the time. He was much more fun than my mother was. They both really wanted to be nurtured, and neither of them was very nurturing." In the film, Mel admits that he stifled Baum's career, who was a dancer in Gentlemen Prefer Blondes. (The pair were married from 1953 to 1962.) "I kept getting her pregnant, and that meant she could not pursue her career, but I could pursue mine," he recalled. "I was very difficult to live with because I was just disgusted with reaching a dead end to my creativity. And I don't blame her for divorcing me. It was just hell living with me. Very unhappy." Rob Reiner Family Guide: Wife Michele and 4 Kids, Including Tracy and Nick In addition to discussing his iconic career and his family life, Mel also opened up about his collaborations and decades-long friendship with Reiner's father, Carl Reiner, who died in 2020. In the documentary, Mel reveals that he was with Reiner the night he died. "I was still hoping that they would put stuff on him and boom, get him up," the director says. "I Just didn't want him to go. I just couldn't - I wouldn't accept it. I loved him so much."