Hi Puppies, we too have an Angel Care monitor and haven't ever had a problem with the sheets. The easiest way to short sheet is to put the sheet across the cot instead of longways. Fold the ends of the sheet a bit and tuck it in across the bed. I also use 2 cloth nappies (flats) to hold the sheet securely in place. So if you picture the sheet across ways with the ends folded so it's not so long and use 2 cloth nappies stuffed down each side of the matress to hold everything tight. Keeps bubbs firmly in place at the bottom of the cot, the monitor works without problem as you haven't got a big chunk of sheet under the matress and everyone's happy!

Good luck for your little man's safe arrival