I imagine that attending your son's investiture would trump any other special occasion, and photos would be guaranteed to go round the world and be displayed at home for many years. Maybe she will look at the photo and reflect that it didn't look as good as she thought. Maybe she'll think she looks wonderful. If it were my son I would make the biggest effort known to man for his sake, as I did for my son's wedding, and the photos we've seen prove that just throwing loadsa money at an outfit isn't the way to go. You can take the girl out of Stevenage (and I have no quarrel with that town unlike LH) but ...