They come every year and save my son-in-law the trouble of pruning, because by the time they've finished eating and buried themselves to pupate, there is nothing left but bare branches.
And woe betide you if you disturb one of them - they hiss and spit most alarmingly.
When they emerge from their pupae they will be Deaths Head Moths, which impressed the children at our barbecue immensely.
So did the cakes - my speciality Flapjack and the Lemony Rice Pudding Cake with Lemon Curd that I made especially for my gluten-intolerant son-in-law.
The occasion was special too - four generations of my son-in-law's family on one sofa - from right to left - his Dad, himself, his son and his grandsons.
My daughter is far too young to be a grandmother, of course, even a "step" one, but she loves it, so I shall have to resign myself to being a step-great-grandmother!