Mask Grease Pencil Layers Across Objects

Hey,

I’m curious whether this is possible at all. I have a circle grease pencil object and am attempting to place eyes on top. I want the eyes to be masked by the head. I know this can be done within a single grease pencil object but I was hoping this was possible between different object as well. I want the eyes to be a separate object so they’re easier to rig alone. There doesn’t seem to be a way to achieve this effect currently? If there is a way could someone share please?

Thanks,
Mitchell