We're in the process of culling down our stuff to prepare our condo for sale, and though we're generally lean with toys, there's plenty we can throw away because LO (3.5) doesn't play with them. I'm slowly doing this when she's not here because otherwise nothing would ever get tossed, and 99% of the time she doesn't even realize they're gone, but there will inevitably be that time that she'll notice something missing. What are some of the ways that you successfully explained toys being gone to kids this age?