[gaming] Sims 3 Haunted by an Invisible Horse

Last week I posted a Sims 3 ISBI legacy over on LJ. More updates will come, but as I was playing earlier, I realized I could hear a horse frantically whinnying over and over, but when I went looking, I couldn't find the horse. A couple days ago, I expanded the house I'm using for the legacy, and I think, somehow, a horse got trapped inside it while I was in building mode, but now I can't find it to get rid of it.

There is an invisible horse haunting my Sims, and I am cracking up about it.

(Though I'll be pretty unhappy if I have to move them to a new lot. I just finished all sorts of changes to this house!)