First create a screen session

screen -S share

List the screen sessions on second device:

# screen -ls
There is a screen on:
	3541.share	(Attached)
1 Socket in /var/run/screen/S-root.

If you simply try to reattach to the screen session you will not be able to:

# screen -r 3541.share
There is a screen on:
	3541.share	(Attached)
There is no screen to be resumed matching 3541.share.

You will need to run the following command

screen -x 3541.share

Anything written on one screen session will now be mirrored on the other