Dear Mary | 12 December 2009

Q. I have a small flat in a northern seaside town which I use when visiting my son, whose own property is an hour’s drive away. He also stays there when visiting for business meetings, so keeps a set of keys for my flat at his home. His 17-year-old daughter recently asked me the address of the flat, without saying why. Then, when last I arrived there, I found La Senza underwear on the floor, strange shampoo in the bathroom and curtains drawn. No doubt in my mind who had been there. (I can definitely rule out my son.) Mary, my son now denies that my granddaughter would ever do such a thing as stay in my flat without permission. Clearly if she had asked, I would have been delighted to allow her to stay, but I’m upset that she didn’t.

So how do I prevent a family row? Should I change the locks?

P.