Get Sub Tasks of a Task

{
  "STATUS": "OK",
  "todo-items": [
    {
      "id": 1,
      "canComplete": true,
      "comments-count": 0,
      "description": "",
      "has-reminders": false,
      "has-unread-comments": false,
      "private": 0,
      "content": "Subtask",
      "order": 2000,
      "project-id": 308424,
      "project-name": "API Documentation",
      "todo-list-id": 1,
      "todo-list-name": "Projects API",
      "tasklist-private": false,
      "tasklist-isTemplate": false,
      "status": "new",
      "company-name": "Teamwork.com",
      "company-id": 1,
      "creator-id": 1,
      "creator-firstname": "Holly",
      "creator-lastname": "McGill",
      "updater-id": 0,
      "updater-firstname": "",
      "updater-lastname": "",
      "completed": false,
      "start-date": "",
      "due-date-base": "",
      "due-date": "",
      "created-on": "2018-11-22T15:03:52Z",
      "last-changed-on": "2018-11-22T15:03:52Z",
      "position": 1,
      "estimated-minutes": 0,
      "priority": "",
      "progress": 0,
      "harvest-enabled": false,
      "parentTaskId": "1",
      "lockdownId": "",
      "tasklist-lockdownId": "",
      "has-dependencies": 2,
      "has-predecessors": 0,
      "hasTickets": false,
      "timeIsLogged": "0",
      "attachments-count": 0,
      "responsible-party-ids": "1",
      "responsible-party-id": "1",
      "responsible-party-names": "Holly McGill",
      "responsible-party-type": "Person",
      "responsible-party-firstname": "Holly",
      "responsible-party-lastname": "McGill",
      "responsible-party-summary": "Holly McGill",
      "predecessors": [],
      "parent-task": {
        "content": "Include updating predecessors in docs",
        "id": "1"
      },
      "canEdit": true,
      "viewEstimatedTime": true,
      "creator-avatar-url": "",
      "canLogTime": false,
      "userFollowingComments": false,
      "userFollowingChanges": false,
      "DLM": 0
    }
  ]
}