A. I wonder what your feelings are about this: you don’t give even a hint of what they might be. I imagine, because you are writing to me, that they are more to do with confusion and concern than outrage or disgust. Which is good. It gives you a better base to work from if you are not battling with strong negative emotions.

Then again, I wonder why you have not already shared this with your wife. Perhaps you think she might react too strongly, or perhaps you feel too shocked to know what you feel. Perhaps, even, you feel ashamed. Sometimes the secrets that we choose to keep say more about the emotions we find difficult to face than the actual matter in hand.

I can see that this would be hard for you, and not simply because he is your only child. It is always hard when we discover that people are different to the picture we have of them. That’s not so bad, in that it might add another dimension, but it takes quite a lot of thinking to accept this newer identity. It also provokes us to think about our own responses and forces us to consider how we feel about things that are outside what society considers the norm. Which, again, is not a bad thing.

I recently did a radio programme with Grayson Perry, the artist who likes to dress in women’s clothing. He is married and has a teenage daughter (who tends to roll her eyes at dad’s little ways). I haven’t met a warmer or nicer man in a long time. One of the reasons he is so engaging is that he has reached a place of absolute self-acceptance. He accepts his need to dress in women’s clothing as merely one part of his character, just as he accepts his artistic ability or brown hair. It is no more important or alarming than that. He also admits that it has an erotic aspect, but accepts that simply as one part, rather than the whole, of his sexual nature. In facing himself fully, he has defused the guilt and shame that might otherwise have crippled him.

I know the situation you face is not easy, but if you can approach it with the understanding that this is just one part of your son’s character, not the whole, you might find the idea more comfortable. Wearing a pair of silk knickers does not change the fact that he is a 6ft hunk of rugby-playing oarsman; it simply changes your perception of it. I am sure, though, that as a parent, you are worried about his future happiness. Many people are shocked or disgusted by the idea of a man who likes to put on women’s underwear, so you may be concerned that, if your son tells them, it will limit his choice of partners. And if he doesn’t, and it is suddenly discovered, it may cause two people unhappiness.

I feel that everybody has a right to a private sexual life. Your son is an adult. I wonder how you would feel if you had surprised him using hardcore pornography or dressed in full S&M fetish latex? In one sense, this is none of your business. In another, it is your business if you feel your son might be troubled by this aspect of his sexuality and need help with it. Guilt and shame can be intolerable emotions, and corrosive to a person’s happiness. Getting things out into the open diminishes their power.

Not being a man, so less conversant with the male psyche, I canvassed a couple of men’s opinions on this. Both are fathers of sons and both said: talk to him, bloke to bloke. My feeling is that you should do so only when you are ready. I feel it would be wrong, for both you and your son, if you have not managed to come to terms with the idea yourself. Until you feel able to accept this part of your son, you might be in danger of projecting your own feelings onto him. It is unlikely that he will change his behaviour just because you know about it. Disapproval will only drive him further into secrecy, and if there is one thing that is likely to destroy trust, it is feeling disapproved of or shamed by those we love.

If you have a relationship question for Sally Brampton, e-mail sally.brampton@sunday-times.co.uk. In case of publication, names will be withheld. We’re sorry, but Sally cannot answer every letter personally

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