I know how he feels. Something similar happened to me a few years ago. My wife and kids were at Grandma's house for the weekend. They did this several times a year and never came home til after 7:00 PM on Sunday. This was my time to crossdress. I would dress all weekend and take it all off at 4:00 or so in the afternoon. Well this particular Sunday I was sitting on the couch watching a movie. The next thing I know my daughter is standing next to me! It's only 1:00! OOPS!!!
She took it all in stride. My wife was mad as hell though. She forgot to call to tell me she would be early, and I forgot to tell her that I would be crossdressing. A communication breakdown. She is supportive of my hobby, but the kids were never supposed to find out.
It worked out fine though. It turns out my daughter likes my crossdressing. She's a teenager now and gives me all kinds of fashion and makeup advice. I do have to keep reminding her that I am in my 40's and not a teenager though. Junior clothes just don't work for me any more! My Son seems okay with it, but doesn't really say much about it.