What to do with this!!

Hi,

I have a little issue with an enclosed area of my garden. We fenced this area off a few years back as my dog used it, but now she has access to the rest of the garden, this enclosed area is redundant. It was used as her toileting area, but I think there must be something else I could do with it. At present it is a fenced area, full of weeds and gravel. Any ideas? My son wants a rabbit, I thought about chickens or ducks, what do you all think?

Regards

Helen.