Thought is to encounter a fairy in a manner that can bring about such a thing, it'd need to be a special encounter. Probably best way to go about it would be encountering a fairy who has ended up in a crawlspace within the home somewhere. Rain fairies would be the most common ones to do this though that doesn't exclude others from messing around a bit (so long as they aren't causing harm nobody will really punish a fairy too harshly).
This is as far as I can really think about this though, writing a whole thing about it would be a whole other mess that involves bridging the gap between a fairy or fairies caught in the home and actual romance.
