Chatterbox: Inkwell

I need writing help!! 

Okay, have any of you read the Borrowers series? If not it’s about tiny people living in humans’ houses and surviving by taking small things from them. Anyways, I have characters and setting developed: it’s about a family of four- a wife and husband, an older brother, and a teenage daughter. They live under the floor of the parlor of a very basic house. The only problem is I can’t come up with a conflict, so basically the plot is going nowhere. If you have any ideas about the plot could you tell me? It could be a natural disaster, or maybe something to do with the humans. Also if I finish the actual story, I’ll try and post it!! By the way, you should check out the books/animated movie!! The movie is called The Secret World of Arrietty and it’s by Studio Ghibli. (And this might get posted twice, I already posted something like this but it disappeared soooo)