Oscar-nominated actress Patricia Arquette is set to take to the witness stand to testify on behalf of her ex-boyfriend during his divorce trial.

The Boyhood star has a son named Enzo with musician Paul Rossi, but they split shortly after the birth in 1989.

Rossi, who remained a present figure in his son's life, went on to marry Kerry-Ann Johnston-Rossi and he is now embroiled in a bitter divorce battle with her.

According to court documents obtained by Tmz.com, both Arquette and Enzo have agreed to act as character witnesses and will testify on Rossi's behalf.

The divorce trial is set for March (15).

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