I have had families leave without picking up their things a couple of times for various reasons. I distributed the diapers and wipes amongst the other children in care and use the few pieces of extra clothing for other children when needed. They come in handy once in a while. Some people donate everything to a charity. Did you send the family an email asking if they are coming to pick up their things? If they don't answer you within a reasonable amount of time you can make the decision what is best for you.