Angelina Jolie managed to keep her double mastectomy a secret for three months by refusing to make any changes to her busy schedule.The 37-year-old actress - who revealed on Tuesday (14.05.13) that she had a double mastectomy and reconstruction in February after learning she had an 87 per cent chance of developing breast cancer because she was identified as having the BRCA1 gene mutation - managed to keep her surgeries a secret by refusing to make any changes to her or her six children's busy schedules.A source told People.com: "Things appeared normal. The kids were in school during the day and attending after-school activities as they always do."The 'Salt' star continued to make public appearances at events while undergoing treatment, including at the 27th Annual American Society of Cinematographers Awards presentation in Los Angeles on February 10.She was also spotted taking her four-year-old twins Knox and Vivienne to the National History Museum in LA with her fiance Brad Pitt just two days before she had major surgery to remove breast tissue and had fillers inserted on February 16.The Oscar-winning actress also travelled to the Democratic Republic of Congo in March to speak to rape survivors.Journalist Cathy Newman, who joined Angelina on the trip, wrote on Channel 4's, website: "I had not the slightest inkling of what she was going through. We travelled for hours to various camps for people displaced by war, along horrendously bumpy, volcanic tracks. For a woman recovering from major surgery, I can only imagine how difficult it must have been."Brad, who has shares four other children, Maddox, 11, Pax, nine, Zahara, eight, and Shiloh, six, with the actress previously revealed that they treated the experience like an "adventure".He said: "We set up our own little post-op recovery that became pretty fun. You make an adventure out of it."[It was] an emotional and beautifully inspiring few months."Read these related stories:Brad hailed Angelina as 'heroic' after undergoing double mastectomy. Angelina Jolie also inspired Queenie Chu to plan to remove her breasts.