Let's say I have this data in my `collection`:

```
{ id: 1, age: 5, name: "Nick" }
{ id: 2, age: 7, name: "John" }
{ id: 3, age: 2, name: "Anna" }
{ id: 4, name: "Peter", children: [1,2,5] }
{ id: 5, age: 25, name: "Mat", children: [3] }

```

I want a query that will return the ***people that have children***, *ordered by* their `age`, in this form:

```
[
 { id: 4, name: "Peter", children: [
   { /* Nick's record */ },
   { /* John's record */ },
   { /* Mat's record */ }
 ] },
 { id: 5, name: "Mat", age: 25, children: [
   { /* Anna's record */ }
 ] }
]

```

**Note:** People in the `children` array of the response should also be ordered by their `age`