Adding a Nest Hello Doorbell to the Camera Group?

I have multiple Nest cameras and I have no problem adding them to my Camera Group. However, I am not given the option to select the Nest Hello Doorbell to add to this group. Has anyone been able to do this or is this omission by design? Thanks!

@tkalberg unfortunately I think it is by design. I have a ring doorbell and I cannot add it to my Camera group as well. Hopefully, they will make a change to add the doorbells. I have x1 smarting camera x2 nest IQ cams and can add them to the Camera Group. You can create a camera group, but you will have to access each camera individually. I would rather be able to access the Camera Group and they all show at the same time.