Much as with Sumo...
Have you tried looking for Sieff's daughter - Sonia - online? She has a website, her name with .com, but I can't open it beyond the Contents page which shows a list of galleries, but rather than opening these, when clicked, just move on to the next gallery and so forth, just one image per gallery.
Is it me, or is she playing cute?
Found other links to her, and she's up there in Vogue and many other magazines of that ilk; makes me quite envious!
Rob
P.S. Pinterest has a collection...