Your SIL sounds like a dictator to me, NangelaMary. How dare he demand what you and your husband do to your spare room. Sounds like blackmail to me! Obviously, when we become grandparents, we are only too happy to adapt to having the grandchildren stay, but not to the extent that it involves so much upheaval. We’ve managed to have our grandchildren stay regularly over the last 21 years, starting with a travel cot in the spare room, which also has a sofa bed for adult visitors, then bunk beds in my OH’s study. Admittedly, we have a lot of cupboard space to accommodate Christmas decorations, accumulations and things of sentimental value. Sorry that you’ve had this most unpleasant ultimatum from your daughter’s husband. He sounds so very controlling to me!