The disappearance of British Museum artefacts prompts the Royal Collection Trust – the largest private assembly of artworks in the world – to conduct a discreet stocktake. Although there is no suggestion of anything amiss, a source says that keeping track of more than one million items can be tricky. The King has a penchant for travelling with his favourite art. One courtier was once taken aback to come face to face with drawings by Queen Victoria and a Flemish oil painting from the Collection in a Royal lavatory.