The `Firework` singer`s parents are evangelical Christian missionaries who wouldn`t read any book to her other than the Bible or let her listen to non-religious music, which had a huge effect on her. Explaining how sheltered her life was by referring to a national chain of health centres, she said: "I didn`t have a childhood. Growing up, seeing Planned Parenthood, it was considered like the abortion clinic. "I was always scared I was going to get bombed when I was there. I didn`t know it was more than that, that it was for women and their needs. I didn`t have insurance, so I went there and I learned about birth control." Katy, 26, added her relationship with her parents has developed, and they are more accepting of each other`s views. She added to Vanity Fair magazine: "I think sometimes when children grow up, their parents grow up. "Mine grew up with me. We coexist. I don`t try to change them anymore, and I don`t think they try to change me. "We agree to disagree. They`re excited about my success. They`re happy that things are going well for their three children and that they`re not on drugs, or in prison." Katy - who has a tattoo reading `Jesus` on her left wrist - added she has always questioned her faith. She said: "I have always been the kid who`s asked, `Why?` "In my faith, you`re just supposed to have faith. But I was always like - `why?` "At this point, I`m just kind of a drifter. I`m open to possibility. "My sponge is so big and wide and I`m soaking everything up and my mind has been radically expanded.