Joanna is expecting her third child (gender a surprise) —a little sibling for Everly Pearl and Mabel Grace.
Joanna writes: "We're really struggling to find a girls name that we both like to go with siblings. I like the names Posie (my favourite but husband hates it), Thea, Delphine (this is my grandmothers middle name).
My husband likes Ivy (too common for me) and Iris (I think sounds a bit too mature and difficult to nickname)""
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Firstly, let me just say that I love every sing name on your list. And the fact that you have Delphine as a family name seems too much of a wonderful gem to pass up.
For the suggestions below, I've been drawn particularly to names with Ls and Es that Everly and Mabel also share as well as different endings to -y and -el.
Ada – Sweet Ada fits the Edwardian revival era of Ivy and Iris and the bell tones of Thea. Genius mathematician and pioneer, Ada Lovelace, makes a great namesake, also.
Alba – A Romance language name meaning "dawn, sunrise" as well as "white, bright, shining". At #175 in England and Wales, it sits in the perfect not-too-hot-not-too-cold bracket that Everly and Mabel occupy.
Anais – A similar name to Iris but with a fresher feel and more nicknamable. Anais has been linked to Anna for centuries, but it is now thought that it is the French form of the Greek Anaitis, their form of the Ancient Persian goddess Anahita whose name meant "pure".
Athena – At #204, Athena is a rising, fashionable choice that sits between Everly and Mabel in the rankings. As the name of the Greek goddess of wisdom, warfare and crafts, she makes for a strong namesake.
Clara – An elegant Roman name with a vintage feel and a feisty style.
Cora – Short, vintage and vowel heavy like Ivy, Iris and Thea. Cora is a small name with a long and rich history that dates back to an ancient goddess.
Delphi – Combining Delphine and Posie, Delphi is the name of the ancient town on the slopes of Mount Parnassus, home of the sacred oracle who was consulted about important decisions throughout the ancient classical world and was considered the centre of the world to the Greeks. The name -- just like Delphine -- derives from Greek delphis "dolphin".
Dulcie – Sweet like Posie, Dulcie -- which literally means "sweetness" -- has been used as a given name since the Middle Ages.
Lara – An elegant literary name with Greek roots. Possible meanings include "sweet, pleasant", "comorant" or "larch".
Lena – An elegant vintage name that's similar in sound to Thea but far less common (#169 vs #46).
Nola – A Victorian revival name which ranks comfortably at #310.
Nova – A Golden Age Hollywood name which ranks in the not-too-hot-not-too-cold sweet spot of #186.
Olive – Sweet Olive is similar in style to Iris but with nickname options of Liv, Livvy or Ollie.
Ophelia – Bold Shakespearean Ophelia has a lovely lyrical sound and a rising profile -- currently at #177.
Polly – Sweet Polly is akin to Posie but may be more to your husband's liking with its vintage style.
Primrose – The lovely Primrose is a lovely Spring flower. As a given name, it can be shortened to Posie, while still sounding as grown-up as Iris.
Rosa – Not only the Latin form of the beautiful rose, Rosa is also the Latinised form of the medieval Roheis meaning "famous, renowned one".It ranks at #154.
Sadie – A bubbly vintage short form of princessly Sarah, ranking at #142.
Seren – A Welsh gem meaning "star" which is sleek and stylish.
I hope this will help spark renewed inspiration for girls' names. Good luck with settling on the perfect name for your new family addition.