My mother was courage itself. She was always looking after my father, who was very ill. When my father died, my mother came back from being Mrs Birkin to being Judy Campbell. She was a stunning actress. She came out of her shell. She was herself again: this very independent, funny, intellectual lady – and was able to perform again, which was her life before meeting my father squashed it out. I took her with me on my tours and we had great fun.
From my mother, I learned the excitement of doing the same thing as she did. From my father, I learned things that have brought great satisfaction in my life. He was a probation officer and in the [second world] war worked for the French resistance; he was a navigator who smuggled people on to the coast of France. He really was an extraordinary hero. He gave me an enormous conscience. [When I was] in a tank in Sarajevo or Rwanda or Burma [doing humanitarian work], I thought, "my father would have done this" – and that he would be proud of me or at least not disappointed, as he was when I became an actress.
Nothing has ever touched on what fun childhood was. Summer holidays were bliss. We made home movies, with real stories in them. My father had such charm and charisma, and made everything so funny.
Thank goodness for my sister, Linda, when I'm stuck or miserable. I love being with her and her boys. When I'm really frightened before going on stage, I call Linda. She's wise, sensible, loving and so comforting.
I had a baby at 19 and was a grandmother by 39. Now, my children lend me their children to take them off to Brittany. It's divine. I'm quite exceptionally lucky. I've never had a week without having all three of my daughters on the telephone. My eldest daughter, Kate [Barry], looks most like me. She's a photographer. She had a Polaroid camera in her hand from a young age and photographed her sisters all the time. Charlotte [Gainsbourg] was so miraculous and true in Jane Eyre – my youngest daughter, Lou [Doillon] and I sat there with kitchen-roll between us sobbing. Lou has been such a darling and so supportive of her sisters, and so intellectual.
My first husband, John Barry, was a composer. I couldn't believe that this sophisticated, talented genius chose me and not any of the other girls. I was so flattered, so excited, so in love with him. Of course, my parents were horrified as he'd been married once and had a daughter with the au pair girl. He had a rather racy reputation. I was only 17. I couldn't believe he'd go off with someone else. When I went back to my parents afterwards, they were very good. They never said "I told you so", they said "come home". They were so happy when I met someone who loved me as much as I loved him and who was so warm. With Serge [Gainsbourg], he had that Russian-Jewish thing of loving my father. Serge fitted in.My brother was crazy about Serge, they had the same sense of humour.
If Serge loved someone, he wrote songs for them. I picked up the song that Brigitte Bardot didn't want him to bring out as she was married, Je t'aime … moi non plus. It was a joy singing what he'd written and to see his face when he was happy with me, but also he was an absolute stinker if I didn't get it. He hit me with a ruler. If you're with your lover in the recording studio, it can be just as hard as it is nice. God, was it painful. He's more famous now than he was when he was alive. It's a very strange feeling to have been with a myth. When I left him, he wrote the most beautiful songs, with great eloquence, about the pain of being left. It was sometimes easier to be his friend. He treated you as an adult for the first time. I was very lucky that he didn't want to stop seeing me and wanted to go on writing for me.
• Jane Birkin sings Serge Gainsbourg via Japan at Cadagon Hall, London on 31January, janebirkin.net/uk, cadoganhall.com/whats-on/2013/01/31
