Attach html to feature group #1079

I am looking to add an HTML legend at the bottom corner of each layer. The legend will be different per layer.

I can add an HTML legend to the base map using map.get_root().html.add_child(<html>), however this will only display the same text for all layer. I am looking instead for a method to attach html to a feature group, ie, something like feature_group.get_root().html.add_child(<html>).