During Installation and device configuration, on 'Link Child' screen, there is a button labeled 'Create Child's Profile' to create a Child Profile.
Here you can map/link device to some existing Child-profile Or you may create a new profile as required.
When you pick the "Create New Profile" option you will see the 'Create Child's Profile' screen. Create a Child's Profile.
Here you need to provide your desired child name, birth year, and gender. After providing the information, hit the 'Create' button. This will create a new child profile.