protected static function childIQ($gender, $father, $mother)
{
// // Son's IQ depends on mother's IQ
// if ($gender == Human::MALE) {
// $iQ = Random::iQ($mother->getIQ(), self::IQ_INHER_VAR, self::IQ_INHER_SD);
// // Daughter's IQ depends on father's and mother's IQ
// } else {
// $averageIQ = ($father->getIQ() + $mother->getIQ()) / 2;
// $iQ = Random::iQ($averageIQ, self::IQ_INHER_VAR, self::IQ_INHER_SD);
// }
$iQ = Random::iQ($mother->getIQ(), self::IQ_INHER_VAR, self::IQ_INHER_SD);
return $iQ;
}