Accessing parent data in MeteorJS

client.html

<template name="garage">
  <h1>Garage: </h1>
  Cars in the garage:<br/>
  <ul>
      {{#each cars}}
        <li>{{registrationNumber}} {{owner}} - <button class="removeCar"></li>
      {{/each}}
  </ul>
</template>

collections.js

{
    _id: "1233",
    name: "My garage"
    cars: [
        {
            _id: "12341"
            registrationNumber: "ABD 231",
            owner: "Sebastian Dahlgren"
        }
    ]
}

garage.js

Template.garage.events({
  'click button#removeCar': function (event, template) {
    Garage.update(
      { _id: template.data._id },
      {
        $pull: {
          cars: {
            _id: this._id
          }
        }
      });
  }
});