I also grew up around large flocks of sheep and found that when you isolate a young lamb and socialize it: lots of fun. Socialized lambs will recognize human friends and will respond to a given name and hang around and play. But after a year or two, after any time spent back with the flock, they forget humans and revert to being one with the herd. Older isolated sheep just get mean and end up being lawnmowers if not mutton. I figured we'd just bred the fun out of them, with a small remaining playfulness coming out while a lamb. I'd be curious to know more about wild sheep.