What happened to my villagers?

Playing Bedrock edition on iPad.

I set up my base about 200 blocks from a village. When I first visited, there were a handful of villagers.

When I returned many game-days later, the village was deserted. As the village was generated with a river running through it, I thought the villagers may have drowned or been attacked by drowned zombies.

So I set about protecting the village with fences and torches, and covering the river to avoid drownings or the Drowned.

To start re-populating I cured two zombie villagers, and took them back to the village. They both found beds.

I then went back to my base to get some food to start breeding them, slept, and when I went back they had disappeared without a trace! Very annoying after all that work.

What has happened to them? Can we say? What else should I have done to protect the new villagers?

There are some zombie groans still coming from underground / the covered river - might the villagers still get attacked?

Solution 1:

Now to start with, have you heard of despawning?

Thanks to the chunk loader, you are only allowed to load a limit of chunks. As you leave that area and the chunk is no longer visible, there are certain instances for these villagers to despawn.

It's better to actually find name tags or trade for name tags, name them and they won't despawn even if you are out of the chunk.

Of course, they might still despawn for other reasons (just like what happened to my horse), but setting a name for them would give extra protection. Just make sure to protect them or they're dead.