Jon Voight was stunned to learn that his daughter Angelina Jolie underwent a double mastectomy earlier this year (13) - because he had no idea about her private health battle. The Salt star has revealed she underwent the preventative surgery in February (13), after doctors warned her she carries the "faulty" gene BRCA1 but the veteran actor was kept in the dark about her diagnosis. Voight reveals he spent time with his daughter and her fiance Brad Pitt over the weekend (11-12May13), when they celebrated her brother, James Haven's, birthday, but Jolie never let her closely guarded secret slip. The Midnight Cowboy star praised his daughter's courageous decision and hailed the actress as an "inspiration" but insisted that he had "absolute" respect for her choice not to inform him about the surgery personally. He tells the New York Daily News, "My love and admiration for my daughter can't be explained in words. I saw her two days ago with my son Jamie (Haven). We all got together for his birthday, with her and Brad (Pitt). But I didn't know. It wasn't obvious at all. I found out on Tuesday morning. I was as surprised as anyone and deeply moved by the way she’s handled this. "She’s a very extraordinary person, the way she examined it and what she shared... I completely understand (her decision to keep her surgery secret and) I want the focus to be on the inspiration."