So I got to work and after a quick search for correct sizing online, turned our 2 double sets into 3 cot sets. I had enough to make 1 set of each colour, then used the extra pieces to create 2 double-coloured sheets, just for fun. Once again this has proven to be a great project for my novice sewing skills.
Here's the two colours just before joining. A bit different from your usual cot sheets! Grin.