I have a data structure that looks like this:

```
var someDataStructure = [
  {
    opts: {_id:1}
  },
  {
    opts: {_id: 2},
    children: [
      {
        opts: {_id: 3},
        children: [
          {
            opts: {_id: 4}
          }
        ]
      }
    ]
  },
  {
    opts: {_id: 5}
  },
  {
    opts: {_id: 6},
    children: [
      {
        opts: {_id: 7},
        children: [
          {
            opts: {_id: 8}
          }
        ]
      }
    ]
  }  
];

```

That's an array of objects, all with an `opts` property, and an optional `children` property. If it exists the `children` property will be an array of the same sort of objects.

Given any `opts._id`, I need to find the `_id` of all parent objects. The `_id`'s I give here are only sequential for convenience. *You may not assume they are sequential integers*

This project is using both jquery and lodash so both of those libraries are available for use.

Example desired output:

* Given `4`, return `[2, 3]`.
* Given `3`, return `[2]`.
* Given `8`, return `[6, 7]`.
* Given `7`, return `[6]`.

I have no problem recursing in and finding the given `_id`. However, I'm feeling dumb and stuck on maintaining the array of parents.