Thanks Tia. How would I hang the piece of fabric? On a curtain rod? Staple gun to the wall?

Let out the futon to the sleeping position pulled away from the wall. Then put it back in sitting position, leaving it in the pulled away location. No one should be moving it. If the child is to sleep there, you can suggest adding some rolled up blankets wedged between the futon and wall for the child's protection. Don't mention your wall issue to them. The blankets will serve two purposes.

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