In his new book 'Taking the Stand', lawyer Alan Dershowitz, who represented Farrow in her case, reveals that Sinatra personally called him to offer his help to Farrow, reported New York Post.
Deshowitz revealed how Sinatra was concerned about his former wife following revelation that Allen cheated on her with her adopted daughter Soon-Yi.
"He immediately got down to business. 'I love Mia. We were married, you know. She's a great girl. Woody's trying to bully her. He can't be allowed to get away with that. What can I do to help?," Sinatra is believed to have told the lawyer.
Aware of Sinatra's reputation, Dershowitz says, "I nervously told him to leave it to the lawyers, and that any approach to Woody Allen would be used against Mia and would likely backfire."
Allen lost the battle with Farrow getting the custody of Ronan and two of their adopted daughters. He went on to marry Soon-Yi and the couple have two adopted daughters.
Farrow recently dropped the bombshell that Sinatra could be the father of her son Ronan, who was believed to be fathered by Allen.