First question is whether she freaks out when put in any kind of enclosure. If you don't know the answer, I'd be hesitant to buy a trailer just assuming it would work. You can explain things to a kid, but not to a dog.

We've got a couple of dogs around that size. They can physically ride in a large basket or the cargo trike, they're just not smart enough to know not to bail out over the front, either.