Why Laravel does not return an item from a collection

I have nested todos. Every todo hasMany todo. I try to get all todos on the same level with staudenmeir/laravel-adjacency-list

I have a collection of todos.

[
    [{
        "id": 30000000,
        "todo_number": 1,
        "order": 1,
        "company_id": 1,
        "todoable_id": 20000000,
        "todoable_type": "issue",
        "title": "1. Todo",
        "children_and_self": [{
            "id": 30000000,
            "todo_number": 1,
            "order": 1,
            "company_id": 1,
            "todoable_id": 20000000,
            "todoable_type": "issue",
            "title": "1. Todo"
        }, {
            "id": 30000001,
            "todo_number": 1,
            "order": 1,
            "company_id": 1,
            "todoable_id": 30000000,
            "todoable_type": "todo",
            "title": "2. Todo"

        }]
    }, {
        "id": 30000003,
        "todo_number": 2,
        "order": 2,
        "company_id": 1,
        "todoable_id": 20000000,
        "todoable_type": "issue",
        "title": "4. Todo",

        "closer": null,
        "todos": [],
        "children_and_self": [{
            "id": 30000003,
            "todo_number": 2,
            "order": 2,
            "company_id": 1,
            "todoable_id": 20000000,
            "todoable_type": "issue",
            "title": "4. Todo"

        }]
    }]
]

return $allTodos[0][0]; shows the following result:

{
    "id": 30000000,
    "todo_number": 1,
    "order": 1,
    "company_id": 1,
    "todoable_id": 20000000,
    "todoable_type": "issue",
    "title": "1. Todo",
    
    "children_and_self": [
        {
            "id": 30000000,
            "todo_number": 1,
            "order": 1,
            "company_id": 1,
            "todoable_id": 20000000,
            "todoable_type": "issue",
            "title": "1. Todo",
            ]
        },
        {
            "id": 30000001,
            "todo_number": 1,
            "order": 1,
            "company_id": 1,
            "todoable_id": 30000000,
            "todoable_type": "todo",
            "title": "2. Todo",
        }
    ]
}

return $allTodos[0][0]->id; shows 30000000 as expected. Till here everything works well.

But if I try to return $allTodos[0][0]->children_and_self; it shows nothing.

If I try to return var_dump($allTodos[0][0]->children_and_self); it shows NULL

Why children_and_self are NULL? What I’m missing?

Answer

JSON response provides snake case results, but Laravel relations are written as camel case.

So as I mentioned in the comment you will need something like this:

var_dump($allTodos[0][0]->childrenAndSelf)