Enter Playmode Options Null Game Objects

I have a Monobehavior that instantiates 10 children from prefabs on Start and stores them in a private variable called _buttons. It initializes a new array on start as well. Everything works fine when I reload the domain and scene. But when I enter playmode without reloading the domain and scene, I get an error about accessing already destroyed game objects.

When I set a breakpoint at the end of the Start method, the array is being created and populated with correctly. However when I set a breakpoint in the method that uses the array, the array is full of null game objects. So it looks like somewhere between Start and Update something is happening to the array.

 

Thanks for the feedback!

Is this an Editor script (marked with ExecuteInEditMode/ExecuteAlways)?
Does the issue persist when you enable scene reload?
Are those objects by a chance use hideflags?
Do you see the Start call in Playmode?