Subgroups require that your groups are linked.
Subgroups allow you to include other groups as the recipient to messages of a parent group. Once groups are linked together you can just drag a group into the Subgroups panel of another group to add it.
To remove a subgroup just click the cross next to its name.
We will ensure any recipients which appear in multi groups only receive messages once.
Message moderation and daily digests also work as expected with subgroups. You can add as many subgroups as you like to a group and we will take care of any cyclic subgroups (A -> B -> C -> A etc).