Advocates for people with disabilities do not care for utilitarian philosopher Peter Singer. This is because Singer has publicly justified killing disabled newborn infants because of their disabilities. In his book Practical Ethics, Singer weighed the moral justifications for taking the lives of disabled babies. He concluded that in severe cases, such as for children with spina bifida, it might well be morally wrong not to take a baby’s life. For less serious conditions, such as hemophilia, Singer concluded that the decision as to whether or not to kill the infant should depend on whether it would make the parents happy, and whether they intended to “replace” the child with another, non-disabled one.