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.
Boys:
Archie Peter Lewis
Atticus
Freddie James
Oscar Lorimer William
William Casimir
Girls:
Eden Mabel
Elizabeth Alexandra Iris (Rosalind Charlotte Alice)
Elora Isabella Edna (Sienna Frances Sybil)
Genevieve Violet (Alfred "Alfie" Oscar & Elizabeth "Beth" Rose)
Lillie Rose (Oscar Tate)
Phoebe Diana Ottilie (Pandora Violet Helen)
Rosa Rae Howkins
Saskia Jane Ottilie (Jonty Julian Antony)
Siena Zita Alexandra
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.