Birth Control ( The Pill )

Does anybody know when it is too soon to put a young girl on birth control. Obviously you can't start them on it right after birth, but my brother and his wife did mention I believe starting their daughter on the pill at the age of ten and a half eleven years of age. I feel that this is too early of an age for someone but at the same time I want to respect the parents decision. I started birth control in my 20's and NOT for the sake of keeping pregnancies at bay. I am not sure how to feel about his. What advice can you give me to help me with this situation