I just put the nest box in with my rabbit. I also provided straw for her and put some in the box to start it and left some out for her to use and work with. I saw her laying in the box and she fits well in there. I thought it was too big but it works great. My daughter and dad made it. Anyway, my concern is that should I have it in there if she hangs in there all day OR is the real concern only if she eliminates in there? This is her 27th day from the mating. Btw...she looks so cute and cozy in there! Thanks!