Validate birthday, parse the age and constellation of valid birthday.
composer require dakalab/birthday
use Dakalab\Birthday\Birthday;
$birthday = new Birthday('2018-12-01', 'zh');
$age = $birthday->getAge();
$constellation = $birthday->getConstellation();
$formatedDate = $birthday->format('d/m/Y'); // 01/12/2018
$normalizedDate = (string) $birthday; // 2018-12-01