How to switch between PHP Classes? : <p>I am currently developing a web app which has following three classes. (One is parent and other two are child classes.)</p>

<pre><code>class Members {} /* Parent Class */

class Group1 extends Members {} /* Child class 1 */

class Group2 extends Members {} /* Child class 2 */
</code></pre>

<p>The requirement is quite simple. All persons in Group 1 or Group 2 <strong>Must be a Member.</strong> But my question is, what should I do if a person in Group 1 decided to move Group 2? Creating a new group 2 object will remove all the past data. But <strong>Everything he/she has done in Group 1 must be preserved.</strong> Any help how to do this in <strong>Proper Way</strong> is highly welcome..!</p>
