I have 2 classes linked together. In a search-method an object (or a list of them) is created and returned.
The structure was build correct in the search-method, but when I assign another value to the mom-object it seams that there are different child-objects.
The following sample shows it:

####################################
#
class Mom
{
	// Properties:

	var $title;
	var $myChild;


	// Methods:

function Mom ($title = "")
{
	$this->title = $title;
}

function init (&$child)
{
	$this->myChild = &$child;
}

function search ()
{
	$mom = new Mom ("test10");
	$child = new Child ();
	
	$mom->init (&$child);
	$child->init (&$mom);

	return $mom;
}

}	# end class Mom


####################################
#
class Child
{
	// Properties:

	var $myMom;


	// Methods:

function Child ()
{
}

function init (&$mom)
{
	$this->myMom = &$mom;
}

}	# end class Child


####################################
#
#   test code:

    $m = new Mom ();
    $mom = $m->search ();
    $t0 = $mom->title;
    $t1 = $mom->myChild->myMom->title;

    echo "$t0 = $t1<br>\n"; # correct values


    $mom->title = "test1";
    $t0 = $mom->title;
    $t1 = $mom->myChild->myMom->title;

    echo "$t0 != $t1<br>\n"; # why are t0 and t1 different?


Is there a bug in my code or in php?
Thanks,
Chris