Javascript json customization

Hi here i am trying to manipulate one json file to below format. I am not able to think how to do that ?

The way i am thinking is not efficient thats why i need hep on this ?

Is there any easy way to do this.

Please have a look

[
 {
    "nid": "61629",
    "title": "K02 - Kiosk Slider - EN",
    "itemsSlider": [
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "en_US"
      },
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "en_US"
      }
    ]
  },
  {
    "nid": "61629",
    "title": "K02 - Kiosk Slider - EN",
    "itemsSlider": [
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "es_MX"
      },
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "es_MX"
      }
    ]
  },
  {
    "nid": "61629",
    "title": "K02 - Kiosk Slider - EN",
    "itemsSlider": [
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "fr_FR"
      },
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "fr_FR"
      }
    ]
  },
  {
    "nid": "61629",
    "title": "K02 - Kiosk Slider - Mix",
    "itemsSlider": [
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "es_MX"
      },
      {
        "nid": "61626",
        "status": "1",
        "titleNode": "01Additional Suitcase - EN",
        "language": "en_US"
      }
    ]
  }
]

THis this the output i am expecting for:
Please have a look Is there any way to achive it?

{
  "es_MX": [
    {
      "nid": "61626",
      "status": "1",
      "titleNode": "01Additional Suitcase - EN",
      "language": "es_MX"
    },
    {
      "nid": "61626",
      "status": "1",
      "titleNode": "01Additional Suitcase - EN",
      "language": "es_MX"
    }
  ],
  "fr_FR": [
    {
      "nid": "61626",
      "status": "1",
      "titleNode": "01Additional Suitcase - EN",
      "language": "fr_FR"
    },
    {
      "nid": "61626",
      "status": "1",
      "titleNode": "01Additional Suitcase - EN",
      "language": "fr_FR"
    }
  ]
}