You say you the bed is used in its flat position.
Solution 1 –
Position the head of the bed against a wall or an item of furniture, so that the pillow does not slide off.
From the photo it looks as though there is room to turn the bed by 90 degrees and use the wall. If not, remove the clutter in the corner behind the bed.
Solution 2 –
Sleep the other way round, so that the metal hoop at the 'foot' can retain the pillow.
If that isn't enough support, stand a sheet of MDF at that end, drill some holes, and use plastic ties to secure it to the metal hoop and the legs. You now have a makeshift headboard.
Answer from Weather Vane on Stack ExchangeFrugal suggestions for preventing pillows falling down between wall and mattress? Currently using cinder blocks and plywood in place of a "frame", then box spring and mattress on top.
Edit to add. We are using cinder blocks instead for extra stability.
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You say you the bed is used in its flat position.
Solution 1 –
Position the head of the bed against a wall or an item of furniture, so that the pillow does not slide off.
From the photo it looks as though there is room to turn the bed by 90 degrees and use the wall. If not, remove the clutter in the corner behind the bed.
Solution 2 –
Sleep the other way round, so that the metal hoop at the 'foot' can retain the pillow.
If that isn't enough support, stand a sheet of MDF at that end, drill some holes, and use plastic ties to secure it to the metal hoop and the legs. You now have a makeshift headboard.
I can think of a few options:
Fit a headboard of their own choosing
It should be relatively easy to sew a couple of bands of elastic onto a pillow case so that the elastic goes around the mattress. If you're having trouble envisaging what I mean, think about a watch with an elasticated strap. The strap hugs your wrist, and the face protrudes. In the same way the elastic hugs the mattress and the pillow in its case protrudes
Consider sewing the pillow case to the bed sheet, if they don't want to change the aesthetic of their sheet/case color matching regularly
If their sewing skills aren't up to this and nowhere locally can help, consider taking a pillow case and make two cuts in the bottom (the bit that touches the mattress when it's in sleeping position) near the closed end. Thread a belt, rope, strap or similar fastening into the open end of the pillow case and out through each hole and then flip the whole lot over and strap the pillowcase to the bed, then fill with a pillow
- perhaps the simplest solution, if they want to go for it, would be to put the bedsheet over the top of the pillow when making the bed