Moving two instances together during placement

Hi,

I have a placement question.

1) Is there a command/constraint that can be set for moving an instance and a desired unconnected spare cell together during placement?

2) Is there a command/constraint that can be set for moving an instance and a desired unconnected spare module (containing multiple spare cells) together during placement?

I have a workaround where I add some padding to the first instance and then move the desired spare modules/cells in that padding region after the initial placement. But it would make my life  alot easier if I can somehow use some constraints that allow them to move together as the design is placed.

Thanks,

Zaman.