eloquent boot not firing only for one class - php

Question

I'm using eloquent for a project and I would like to delete articles. The problem is that the database is complicated. There are articles, that have article_lvl1 and article_lvl1 have article_lvl2. When I delete an article the event functions work fine :
<?php
namespace app\model;
class Article extends \Illuminate\Database\Eloquent\Model
{
public static function boot()
{
parent::boot();
// cause a delete of a product to cascade to children so they are also deleted
static::deleting(function($article)
{
$article->ArticleNiveau1()->delete();
$article->ArticleNiveau2()->delete();
});
}
public function ArticleNiveau1()
{
return $this->hasMany('app\model\ArticleNiveau1', 'id_article');
}
public function ArticleNiveau2()
{
return $this->hasMany('app\model\ArticleNiveau2', 'id_article');
}
protected $table = 'Article';
public $timestamps = false;
protected $primaryKey = 'id_article';
}
But an article can also have article_Informations, which can have article_Date. My problem is that everything in the boot functions executes fine on delete, but not the article_Date. Here is the code :
<?php
namespace app\model;
class Article_Informations extends \Illuminate\Database\Eloquent\Model
{
public function Article()
{
return $this->belongsTo('app\model\Article', 'id_article');
}
public function ArticleNiveau1()
{
return $this->belongsTo('app\model\ArticleNiveau1', 'id_nv1');
}
public function ArticleNiveau2()
{
return $this->belongsTo('app\model\ArticleNiveau2', 'id_nv2');
}
public function Article_Date()
{
return $this->hasMany('app\model\Article_Date', 'id_info');
}
public static function boot()
{
parent::boot();
// cause a delete of a product to cascade to children so they are also deleted
static::deleting(function($info)
{
$info->Article_Date()->delete();
});
}
protected $table = 'Article_Informations';
public $timestamps = false;
protected $primaryKey = 'id_info';
}
I don't know why, it's the only event that is not fired on delete.
Can someone explain me ?