If the bedroom in question had not only a lock but an en suite bathroom, I suspect the private crapper was the real reason. Many older people have issues, that they may not be comfortable talking about, requiring using the bathroom several times a night.

When my father-in-law died, we invited my mother-in-law to live with us and voluntarily let her have our bedroom, which was bigger than the guest room and had its own bath. There were a few reasons for this.

First of all, she spent a good part of her day in the bedroom where my husband and I only used ours for 7 or 8 hours a day. She smoked, so we liked the idea of confining that activity to one area of the house. Also, for as long as I knew her, she had longed for an en suite bathroom but had never enjoyed that luxury. She’d been through a lot care-giving for her husband in the last years of his life. It seemed a simple thing to make that dream come true.

The woman who refused to let her mother-in-law use her bedroom probably had her reasons, but unless it was more compelling than “I don’t want to”, she could have saved herself and her marriage a lot of stress if she had backed down. Then she could put a lock on the guest room door for the next time her mother-in-law visits and everyone’s happy.

My mother-in-law was a very difficult person. My friends thought I was crazy to have her live with us, but she had her good qualities, too. Besides, she is the only grandparent of my son’s that he got to know. She adored him and he learned about compassion, compromise, and charity by having her around. There’s no simple answer to the question of whether or not to accommodate such a request from an in-law. People and situations differ. You just have to do what you think is right and suffer the consequences with grace and good humor.