src/Models/Contact.php
public function setBirthdateAttribute(Carbon $birthdate = null)
    {
        if ($birthdate === null) {
            return $this->attributes['birthdate'] = null;
        }

        return $this->attributes['birthdate'] = $birthdate;
    }
public function setBirthdateAttribute(Carbon $birthdate = null)
    {
        if ($birthdate === null) {
            return $this->attributes['birthdate'] = null;
        }

        return $this->attributes['birthdate'] = $birthdate;
    }
public function setBirthdateAttribute ( Carbon $ birthdate = null ) { if ( $ birthdate === null ) { return $ this -> attributes [ 'birthdate' ] = null ; } return $ this -> attributes [ 'birthdate' ] = $ birthdate ; }
set Birthdate.

@param Carbon $birthdate Carbon parseable birth date
set Birthdate .