Small Atlantean pets don't get along well with each other, so it's necessary to raise them before a new baby pet can join.

To grow a pet, you'll need a special resource - Lu'mian.
Lu'mians can be found:
- During expeditions in the permanent islands
- In the Daily Adventure island
- In a temporary adventure (if any)

After you collect enough Lu'mians, open the Nursery, tap on a pet and tap "Upgrade". You need to upgrade your pet 3 times before it becomes fully grown.

A hint for Lu'mian will appear in the resource menu when you travel to a new Daily Adventure island.

Before moving on to the next location, Lu'mian can be found near the Guardian Statues.