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:
Alfred George Rupert (Annabel)
Caspian Alexander Owen (Hermione & Ionia Enna Mary)
Charles Patrick Burwood (Florence)
Charles Philip Arthur
Freddie
George Henry Samuel (Hugo Thomas Oliver & Jemima Matilda Jane)
Henry Peter Mark Down
Jasper Maximilian Jafari (Felix Balthazar Jafari)
Leo Joshua
Wilbur Thomas Owbridge
Girls:
Charlotte Beatrice
Dusty McRae (Ferris Scott & Billy Peregrine)
Hebe Agnes Eve (Juno Zennor Boudicca)
Hebe Rose Madeleine
Hope Eva Lupe (Rafe Arthur Ziggy)
Isla Dorothy
Martha Elizabeth
Olive March (Ada Jane)
Ottilie Jayne (Thomas "Tommy" Crispin)
Stevie Janine
Tessa Faith (Penelope Canning; half sibs: Rose, William & Alexander)
Twins:
Angus David & Kitty Clare (Lily Rose)
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.