Belongsto有条件 - laravel 4

I have 2 tables

1. Album

   id |isactive| name

2. Gallery

   id |album_id| is_cover

One Album may have multiple Gallery

I need to pull the cover photo of each album which is active

class Gallery extends \Eloquent {

 public function Album() {
        return $this->belongsTo('Album')->where("is_active","=","Y");
    }
    // Add your validation rules here
    public static $rules = []

    // Don't forget to fill this array
    protected $fillable = []
}

my ORM is as below

Gallery::with('Album')->where('is_cover','=','Y')

Since i have already appended is_active='Y' on model but still it is showing all albums(i mean inactive albums are also showing)