One of the issues the whole setter/getter convention creates is that, for instance, I'm now reluctant to write a setter method that does more than just set the field value [1], because some other programmer or some tool might expect that it is no more than a property mutator.
[1] Example: child.setParent(parent) would perform parent.children.add(this)
[1] Example: child.setParent(parent) would perform parent.children.add(this)