How to create sub galleries
Sub galleries are made up of a parent gallery and then unlimited child galleries. Each child gallery is a separate gallery assigned to the parent.
Create your parent gallery. Go to Sunshine > Galleries > Add New. Enter the name of your parent gallery, click Publish.
Create your first sub gallery. Go to Sunshine > Galleries > Add New. Enter the name of your child gallery, select the parent gallery, click Publish.
Optionally enter a number for the Order field to specifically order your child galleries from lowest number to highest.
Repeat adding child galleries as many times as needed.