We brought Wrigley home as a puppy and we used a baby playpen when we were gone and a crate for sleeping at night. Wrigley HATED the playpen and would cry, she has separation anxiety and would chew the drywall and baseboards when she was free to roam! She would also climb out, so we had to buy a top for it.
We stopped using it once she outgrew the chewing and stopped having potty accidents!
When we brought Camden home, she was already two and we used the playpen for her as well, but she literally could jump up on the edge and scale down the side and get out!
So we bought a bigger crate for her when we are gone because she is still accident prone and her and Wrigley get into tiffs!
They both have their smaller crates for sleeping and they LOVE them and will go in them during the day! At night when they are tired they will sit and stare at you sometimes and I know they are telling us they want to go to bed!
