We have a 30yr old pony where I board like that. Since she is 30 and a really sloooow walk is about all she is good for, she gets to meander around the property. She basically goes from turnout to turnout, talking, squealing, backing up to the gates and squirting.
She's "confused" to say the least, if I bring my mare out, she's right up her butt, following and talking. Put my mare in cross ties and she's backing up to her.
All the horses seem to realize she's not quite all there, none of them are in the least bit bothered by her, even those who would NEVER allow a horse to be up their butt. After a bit, some will get this look on their face like "would someone PLEASE remove this loony toon" and then we just chase her out of the barn and she goes back to pacing around between turnouts.
It's actually pretty funny!