Roost within a doghouse??? Help!!!

I have four happy laying hens.  I also have a 4-month old pullet.  She's too big for a kennel now, but the older ladies won't accept her yet.  We got a 6x6 foot chain link pen for the young one (Sunny) and put it right up against the other run, so they can safely acclimate and get accquainted.  I was able to get a large insulated dog house to keep Sunny warm in her pen, BUT I don't know what to do about her roost!  Any suggestions would be helpful!

The dog kennel she's in is about 3 feet tall, and her current roost is aobut 18" off the floor, and she's very happy on it.  I'll be elevating the dog house, with a ladder/plank up to it, but I'm wondering if she'll still use the roost if it's in the secluded part of the dog house.

Any thoughts?  Experience?  Having a single chicken in winter is hard!

Thank  you!  I went ahead and put the roosting bar in the doghouse, and Sunny does like it. At night, though, she's not going in her doghouse/coop without assistance.  She wants to fly up on TOP of her coop and roost there (her coop is inside a chainlink enclosure with a roof -- chain link plus tarp).  

I worry about her getting cold.  Is that silly?  I wonder if she's scared to go in the coop because it's pitch black in there...  Will she have sense enough to go in there if she's cold, even though it's dark in there? 

Thank you!

That is a great idea -- thank you!  Sunny and the biggest hen (Velma, of course...!) spar through the fence, but when Velma does that one of the smaller chickens pecks on Velma's head.  She (Red) might be a good candidate to go in with Sunny.

Thanks! 

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