Add code-generated material and Sprite to Instantiated Prefab

Greetings all,

I'm looking to add an Instantiated Material and a new Sprite (both generated at runtime) to an Instantiated Prefab so I can use PrefabUtility.SaveAsAsset to accomplish having randomized assets at runtime.

I've read that you do so (or at least did in the past) by something like ChildObject.transform.parent = InstantiatedPrefab.transform but Materials and Sprites don't have transforms.

How would I do this via code?

Thanks!