php pseudo-random distribution in a loop

I have some code that generates a random output based on prior parameters from different arrays

Data setup:

$persons = array("Old", "Young", "Child");
$moods = array("neutral", "happy", "sad");
$newarray= "";

shuffle($persons );
$persons2 = array_merge(...array_fill(1, 92, $persons ));
$persons2 = $array = array_slice($persons2, 1, 30);

shuffle($moods);
$moods2 = array_merge(...array_fill(1, 92, $moods));
$moods2 = $array = array_slice($moods2, 1, 30);

The desired output is an if-loop that generates strings of equally many old, young, and child objects that are each an equal amount of neutral, happy, and sad - something like

for ($x = 0; $x <= 30; $x++) {

$mood = $moods2[$x % (count($moods2))];
$person = $persons2 [$x % (count($persons2))];
$newarray .= "|".$person.",".$mood."|";

  }

The problem with this code is that it does not ensure that the moods "happy", "sad", "neutral" are combined evenly with the person categories "Old", "Young", "Child". The desired output is something like

$newarray= "|Old,happy||Old,sad||Old,netrual||Young,happy||Young,sad||Young,netrual||Child,happy||Child,sad||Child,neutral|"; 

such that there is 30 iterations and the possible persons/moods combinations occur equally frequently.

Not that I would also like that final output to be randomly ordered and that the code should work even when changing the number of iterations of the for-loop.