I have a 7x11 dog pen that I am using to house my two silkies and two leghorns in there i also have their coop that is raised high enough that they can freely walk around under and eat as this is where their feeder/waterer hang.My question is could I add another two chickens in this space ? I'd like to have a barred rock.Their coop is as wide as the pen so I'm sure thered be enough room in there just wondering your opinion on the ground space.Thank you.