Laravel pass parameter to its distant relationship (translate children) - php

Question

I have categories with id, parent_id, slug , pivot table category_language which columns are id,category_id,language_id,value
As you can see I can translate parent category, but can't send desired $lang_id to children translations, so each children having all translations
here is what I get:
{
"id": 1,
"parent_id": 0,
"slug": "personal-computers",
"created_at": "2019-12-27 15:05:31",
"updated_at": "2019-12-27 15:05:31",
"children": [
{
"id": 3,
"parent_id": 1,
"slug": "accessories-for-pc",
"created_at": "2019-12-27 15:05:32",
"updated_at": "2019-12-27 15:05:32",
"translations": [
{
"id": 1,
"code": "en",
"name": "English",
"pivot": {
"category_id": 3,
"language_id": 1,
"value": "Acc for PC",
"id": 7
}
},
{
"id": 2,
"code": "ru",
"name": "Русский",
"pivot": {
"category_id": 3,
"language_id": 2,
"value": "Аксессуары для ноутбуков и ПК",
"id": 8
}
},
{
"id": 3,
"code": "ro",
"name": "Romana",
"pivot": {
"category_id": 3,
"language_id": 3,
"value": "aksessuari-dlya-noutbukov-i-pk-ro",
"id": 9
}
}
]
}
],
"translations": [
{
"id": 1,
"code": "en",
"name": "English",
"pivot": {
"category_id": 1,
"language_id": 1,
"value": "PC",
"id": 1
}
}
]
}
Controller:
return Category::with('children')
->with(array('translations'=>function($query) use ($lang_id){
$query->where('language_id',$lang_id);
}))
->where('parent_id',0)->first();
Model
class Category extends Model
{ ..
public function translations()
{
return $this->belongsToMany('App\Models\Translation','category_language', 'category_id' ,'language_id' )->withPivot('value','id');
}
public function children()
{
return $this->hasMany( 'App\Models\Category' , 'parent_id' , 'id' )->with('translations');
}
}

Answer 1

you can add condition in children method
public function children()
{
return $this->hasMany( 'App\Models\Category' , 'parent_id' , 'id' )->with('translations')->where('language_id', 1);
}

Answer 2

Dry7 answer was close to the one I've implemented later, so I upvoted him.
Finally in model I've added: ...->where('language_id',helper_SetCorrectLangIdForQuery());
and function helper_SetCorrectLangIdForQuery is using global helper of Laravel request()->lang . If lang=enz, than it takes default language from another helper.