up.html#FlxGroup">FlxGroup</a></code> will try to replace a <code>null</code> member of the array first.
Failing that, <code><a href="../../flixel/group/FlxGroup.html#FlxGroup">FlxGroup</a></code> will add it to the end of the member array.
WARNING: If the group has a <code>maxSize</code> that has already been met,
the object will NOT be added to the group!</p><p class="javadoc">Parameters:</p><table class="table table-bordered params"><tr><th style="width:25%;"><code>Object</code></th><td><p>The object you