@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class Person implements Serializable {
    @Id
    private Long id;
    private String name;

    @OneToOne(mappedBy="marriedTo")
    @XmlIDREF
    private Person marriedTo;
    @ManyToOne
    @XmlIDREF
    // For the sake of simplicity, Persons only have one parent
    private Person parent;
    @OneToMany(mappedBy="parent")
    @XmlElement
    @XmlIDREF
    private List<Person> children;

    public Person() {
    }

    public Person(Long id, String name) {
        this.id = id;
        this.name = name;
    }

    @XmlID
    private String getStringId() {
        return Long.toString(id);
    }

    // OTHER GETTERS AND SETTERS
}