Midi Bed With Storage These mid sleepers with storage make a great multi-functional piece for children's bedrooms. These beds that are low in size take the standard UK single mattress and put with plenty of storage beneath the mattress. Many come with the pull-out trundle, which is great for sleepovers. https://www.bunkbedsstore.uk/products/kidsaw-white-3ft-cabin-bed-with-multi-drawer