Madeline Kahn knew how to play it for laughs in movies (Blazing Saddles) and on TV (

Cosby), but those close to the late actress remember her as a very serious-minded person who suffered from a troubled relationship with her mom.

"Madeline thought of herself as having had a very difficult childhood and there were a lot of feelings left over from that childhood," says close friend Gail Jacobs on an upcoming Lifetime Intimate Portrait on the star (Oct. 2, 7 pm/ET). "She was very wise about certain things but she was extremely vulnerable, extremely fragile. Madeline was always concerned about the money that she had to earn to keep things going for her mother and to keep her mother happy."

A wannabe performer, Paula Kahn agreed to an interview with Lifetime and confessed that she had a hard time accepting the successful star as her daughter. "I always saw her as another actress," she says of Madeline, who died of ovarian cancer last year at age 56. "I guess there was this competition between us. She never wanted me to perform because I think she felt that it was a threat to her identity. So, I never did."

But Madeline's brother, Jeffrey, counters that their mother's account is not entirely accurate. "Paula tried a number of times to get Maddy to help her further Paula's career and Paula always felt that she was the true undiscovered talent in the family."

Prior to her death, Madeline actually produced her mother's one-woman play at L.A.'s Westwood Playhouse. Among those in the audience was Mel Brooks, who directed the younger Kahn in Blazing Saddles. "It was an interesting evening," recalls Brooks. "Her mother always felt that something screwy happened. You know, 'How come my daughter became so famous and I didn't when we know I'm the real talent here?'"