When the weather is frightful, warm up the afternoon with a sort of sauna. Fill the tub with warm water, cover the bathroom floor with towels (so you just won't care what happens) and let your kids bathe their dolls and all their tiny clothes. Use a mild shampoo, or buy a box of a gentle baby clothes detergent, and set up a drying rack with clothespins.

Have on hand a few "beauty" products for after the bath: combs, hair ribbons, talcum powder, maybe even a few preemie diapers (nothing makes old dolls so attractive as real diapers). A car wash for miniature cars can be equally fun, especially if you have a handheld shower nozzle. Afterward, organize the sparkling fleet for a car show.