groupSiblingsByKeyValue.js

const groupSiblingsByKeyValue = (arr, k, v) => {
  return arr
    .map((o, i, a) => {
      if (o[k] === v) {
        let j = i;
        const group = [];
        while (a[j][k] === v) {
          group.push(a[j]);
          a[j] = false;
          j++;
        }

        return group.length > 1 ? group : o;
      } else {
        return o;
      }
    })
    .filter(Boolean);
}