JSON object issue: Uncaught SyntaxError: Unexpected token

Question

I'm trying to make a variable using data from a JSON file, though it keeps showing as undefined. inspection shows the options object with the following error:

The goal from this code is to configure a product using the first JSON object and then pull in extra information about the product options using the second json object.

The code should output the title of

"cover-silk": ["150gsm-silk-cover"] 

which is stored in the second JSON object

The variable childTitle should = "150gsm"

productData = {
  "product": [{
    "name": "booklet",
    "section": [{
      "coverStock": {
        "cover-silk": ["150gsm-silk-cover"]
      }
    }]
  }]
}, {
  "section2": {
    "coverStock": [{
      "title": "Cover Stock",
      "options": [{
        "cover-silk": {
          "title": "Silk",
          "childOptions": {
            "150gsm-silk-cover": {
              "title": "150gsm"
            }
          }
        }
      }]
    }]
  }
};

var key = productData.product[0].section[0];
var keys = [];
for (var k in key) keys.push(k);

var len = keys.length;
for (var i = 0; i < len; i++) {

var option = productData.product[0].section[0][keys[i]];

  var secObj = (option);
  var secObjArray = [];
  for (var k2 in secObj) secObjArray.push(k2);

  var len2 = secObjArray.length;

  for (var j = 0; j < len2; j++) {

    var childTitle = productData.section2[keys[i]][0].options[0][secObjArray][j].title;
    console.log(childTitle);

  }
};

Answer 1

I have made a lot of changes. The whole structure wasn't right. Check out the comments below and working snippet too:

1. The indices are all wrong.
2. The original JSON was wrong.
3. Changed a lot. Better to use Diff.

Snippet

var productData = {
  "product": [{
    "name": "booklet",
    "section": [{
      "coverStock": {
        "cover-silk": ["200gsm-silk-cover", "250gsm-silk-cover"],
        "cover-gloss": ["300gsm-gloss-cover", "250gsm-gloss-cover"]
      }
    }],
    "section2": {
      "coverStock": [{
        "title": "Cover Stock",
        "options": [{
          "cover-silk": {
            "title": "Silk",
            "childOptions": {
              "150gsm-silk-cover": {
                "title": "150gsm"
              }
            }
          }
        }]
      }]
    }
  }]
};

var key = productData.product[0].section[0];
var keys = [];
for (var k in key)
  keys.push(k);
var len = keys.length;
for (var i = 0; i < len; i++) {
  var option = productData.product[0].section[0][keys[i]];
  var secObj = option;
  var secObjArray = [];
  for (var k2 in secObj)
    secObjArray.push(k2);
  var len2 = secObjArray.length;
  for (j = 0; j < len2; j++) {
    var childTitle = productData.product[0].section[0][keys[i]][secObjArray[j]][0];
    console.log(childTitle);
  }
}

Diff:

If you are interested, this is the Diff: