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:
Arthur David Ross
Arthur George Alexander
Douglas Hume Mick (Clementine Charmian Mary)
Frederick Oscar James (Otis Perceval Peter & Nancy Agnes)
Gus Henry Napier (Wilbur Ivo Gordon)
Harry Robert Phillip
Horatio Buist
Jacob Oakley Saban
Kit Henry
Kristo Ruman (Leo Edward Krassimirov)
Marceau Richard Gilles (Celeste Suzanne Marie & Colette Marguerite Helen)
Maximus Montgomery Roche
Xanthus (Acacia, Leander & Thalia)
Girls:
Alicia Grace Isabella (Sophia Olivia Charlotte)
Cadi Rhys (Efa Rhys) -- dad's fn is Rhys.
Clover Anne
Dusty June
Marina Edith Irene (Frederick & Florence)
Ottilie Florence
Romilly Rose
Romy Lita Camilla -- middle names are for grandmothers.
Saorla Ellen (Caragh Joan)
Tabitha "Tabby" Hazel (Theodore "Teddy")
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.