required_with? https://laravel.com/docs/12.x/validation#rule-required-with
$rules => [
'job_title' => 'string|max:50',
'employee_name' => 'required_with:job_title|string|max:30',
];
In fact, you can apply any complex logic you want: https://laravel.com/docs/12.x/validation#complex-conditional-validation