JSON Array with Key

Hello Everyone, I’d like to once-again call on the wisdom of the community.

I’ve been trying to build a workflow to produce a JSON array which looks like the example below. I’ve been fiddling with it for quite a while and still can’t get it right. I’ve been trying to work on the array from the ‘inside out’, but the thing that’s tripping me up is the siblingId element at the top. I’ve been trying to set it up as a key but the square and curly brackets just never quite line-up properly.

Does anyone know how to achieve this result in a workflow and can give me some advice? Thank you all in advance!

Cam

[
  {
    "siblingId": 564480076736388,
    "cells": [
      {
        "columnId": 2517104256673668,
        "value": "New Employee Name"
      },
      {
        "columnId": 7020703884044164,
        "value": 99999
      }
    ]
  }
]