Prefab within a prefab

Let’s consider I have a prefab called Small, and then I make a prefab called Big which include inside the prefab Small.

Will this portion of Big be connected to Small or the connexion will follow only Big?

In other words, a modification on Small will affect Big (since it was created using Small)?

If you make Small a child of Big, they are different prefabs.

But if you apply the changes on the Big prefab after setting Small as it child, that whole object becomes the Big prefab and the Small prefab conection is lost. Or if you create an object (not a prefab), set Small as a child and then drag to make the object a prefab, the whole object becomes a prefab.

This means you can’t have nested prefabs as assets, you can only nest them in the hierarchy. That’s a feature that everyone wants but it’s not yet implemented. There are plugins to achieve this but I’ve never used them.