Below is a round-up of the birth announcements from British newspapers. Sources include a national paper (The Telegraph, The Times) and a broad range of local newspapers from across England, Wales, Scotland and Northern Ireland.
Sibling names are in brackets. No official surnames are included; any name ending in a surname is actually a middle name.
Boys:
Ivo John Cooper (Arthur Michael R & Hermione Grace Caroline)
Leo Matthew
Max Charles Dilwyn
Ranulph (Rupert)
Ranulph Bruce John
Rowan Edgar Flowers (Eric Gerald Stanley & Daphne Cordelia Dorothy)
Wilfred Hector William (Ottilie Rose Victoria & Fenella Willow Clementine)
William Hamish Lindsay
Girls:
Aurora Fleur Irene Bide (Ottilie Leonora Rose Delap)
Eilidh Ann (Logan Kenneth)
Hattie Sofia Patricia
Honor Ianthe (Hugh)
Sienna May
Twins:
Axel Kazimir & River Valentina
I cross-reference older BAs to find the full names of the siblings, however often they are missing (especially the eldest siblings, or for half-siblings) which explains why you will sometimes see something like: George Henry (Lucy, Emma & Jack Arthur). "Lucy" and "Emma" may well have middle names as well; I simply cannot find them online.