Hm. They're not much for fighting, at least, not at first. But I've started to warm up to having her around. She's learned not to run around at my feet anymore...

[ And she carries her around sometimes, but, no one has to know that. ]

I believe it works a little differently. From my understanding, you just show an Evolutionary Stone to a Pokemon and that's enough to make it change. But Happiny needs to hold the stone while levelling up before it evolves...pretty sure it's an Oval Stone. Looks kind of like an egg. ...Makes sense, considering how much it seems to love rocks that are egg-shaped. Must be like looking for sand in the desert...