Get Size of Gameobject without Mesh or Collider

I’m trying to get the size of a gameobject, but the GO in question is a parent gameobject which is holding multiple child GO’s. The parent GO is only there for the purpose of grouping them as one. It doesn’t have a mesh renderer or collider. It only has the script that is trying to find the size.

How can I find the size of the group of gameobjects? Without manually creating a collider that encompasses the bounds. At that point, my goal would easier be achieved by manual entry, which I’m deeply trying to avoid as I have a huge variety of objects.

What type of object are you trying to get the size of?