Michael Corleone communing with the big purple dinosaur? "I catch Barney every once in a while," Al Pacino admitted last year. Of his twins, son Anton and daughter Olivia, who turned 2 on Jan. 25, Pacino said, "They have certainly given my life a lift."

Now Pacino, 62, is fighting to keep them in his life. The actor filed suit last month in New York City family court seeking joint custody and liberal visitation rights from the twins' mother, actress Beverly D'Angelo, 51. "He doesn't want to fight with her," says Pacino's friend, writer Lawrence Grobel. "Unfortunately he has an issue with [D'Angelo] where he can't have as much individual time with the kids as he would like." A friend of D'Angelo's, expressing surprise Pacino took the spat to court, calls it a dispute between two temperamental people "who are madly in love with each other. I guess you can emphasize the 'madly.' "

The move marks an unhappy turn in an unconventional relationship. The never-wed Pacino—who has a daughter, Julie, 13, with former flame Jan Tarrant—began dating D'Angelo six years ago, and she conceived the twins through in vitro fertilization. Though they have separate homes, they still spend time together at his spreads in Sneden's Landing, N.Y., and Manhattan. "He's always reading his scripts while the kids are running around in the courtyard," says a Manhattan neighbor.

With hearings set to begin Feb. 24, Grobel feels his famously private pal may still avoid a public tug-of-war. Pacino "is trying to work things out," he says. "He loves these kids as much as he loves anything in his life."