Layers in sub-tree do not appear.

[shober-a]

I am trying to add layers as children (geoJSON layers), but they do not appear when the boxes are checked. (They do appear if part of the top layer). That is, this works:

{
  type: 'leaflet',
  name: 'Boundaries',
  layer: placeGeom,
},
{
  type: 'leaflet',
  name: 'Field',
  layer: L.geoJSON( ... ),
}

but this does not:

{
  type: 'leaflet',
  name: 'Boundaries',
  layer: placeGeom,
},
{
  type: 'leaflet',
  name: 'Fields',
  children: [
    {
      type: 'leaflet',
      name: 'Field',
      layer: L.geoJSON( ... ),
    },
  ],
},

Am I missing something obvious?