Most people believe that parents have moral rights and responsibilities regarding their children. These rights and responsibilities undergird the nuclear family and are essential to the flourishing of its members. However, their basis and contents are hotly contested. Do a child's genetic parents have a right to parent her? The importance of genetic ties is affirmed by many people's gut responses, everyday talk, and many court decisions, but the moral justification for tying parenthood rights to genetics is unclear. Parents are routinely permitted to make far-reaching decisions about their...