Midi Bed With Storage These mid-sleepers that have storage are a fantastic multi-functional piece for children's bedrooms. These beds that are low in size use the standard UK single mattress and put with plenty of storage below the bed. Many come with the pull-out trundle, which is great for sleepovers. https://www.bunkbedsstore.uk/products/solid-pine-wood-kids-bunk-bed-with-slide