Hello!We were totally set on using [name]Isla[/name]. Although I still really it like I am now considering using a different name. These are what I have so far:
[name]Marissa[/name]
[name]Matilda[/name] (nn [name]Tilly[/name])
[name]Isla[/name]
[name]Harriet[/name] (nn [name]Hattie[/name])
[name]Harper[/name]
Let me know what you think.
Thanks!
For a sister to [name]Olivia[/name], I keep thinking of
[name]Emily[/name] or [name]Emilia[/name]
[name]Marissa[/name]
[name]Camilla[/name]
I would stick with [name]Isla[/name]! It’s a beautiful name and goes so well with [name]Olivia[/name].
I think [name]Isla[/name] is a gorgeous name.
From your list, i really like [name]Matilda[/name] and [name]Harriet[/name], both of which were on my list, but [name]Matilda[/name] has just been scratched off as it is getting a bit popular in the UK at the moment. [name]Harriet[/name] nn [name]Hattie[/name], however, is towards the top of my list. I think its divine x
From your list, I really love [name]Matilda[/name], [name]Harriet[/name], and [name]Isla[/name].
Some more you may like:
Along the lines of [name]Matilda[/name] and [name]Harriet[/name]:
[name]Adeline[/name]
[name]Annabel[/name]
[name]Alice[/name] (although there’s a brand of clothing called [name]Alice[/name] + [name]Olivia[/name])
[name]Beatrice[/name]/[name]Beatrix[/name]
[name]Cora[/name]
[name]Charlotte[/name]
[name]Clementine[/name]
[name]Cecily[/name]
[name]Clara[/name]
[name]Emmeline[/name]
[name]Genevieve[/name] (has [name]Olivia[/name]'s V sound, though)
[name]Georgina[/name]
[name]Hazel[/name]
[name]Iris[/name]
[name]Josephine[/name]
[name]Juliet[/name]
[name]Mirabel[/name]
[name]Nora[/name]
[name]Penelope[/name] (nn [name]Nell[/name] or [name]Poppy[/name])
[name]Pearl[/name]
[name]Rosaline[/name]
[name]Rose[/name]
[name]Rosalind[/name]
[name]Stella[/name]
[name]Tess[/name]
[name]Tabitha[/name] (nn [name]Tibbie[/name])
At least slightly exotic sounding like [name]Isla[/name]:
[name]Arabella[/name]
[name]Aurora[/name]
[name]Calla[/name]
[name]Clarissa[/name]
[name]Daphne[/name]
[name]Esme[/name]
[name]Francesca[/name]
[name]Gemma[/name] (unless you’re in the U.K., where it’s apparently dated)
[name]Jessamine[/name]
[name]Juliana[/name]
[name]Mariana[/name]
[name]Marielle[/name]
[name]Zara[/name]
Good luck! 
[name]Matilda[/name] and [name]Harriet[/name] seem too vintage to me, and [name]Harper[/name] seems too unisex. [name]Isla[/name] and [name]Marissa[/name] are just so-so to me…
[name]How[/name] about another [name]Shakespeare[/name] name?
[name]Celia[/name], [name]Rosalind[/name] - As You Like It
[name]Francisca[/name], [name]Juliet[/name] - Measure for Measure
[name]Bianca[/name], [name]Emilia[/name] - [name]Othello[/name]
[name]Iris[/name], [name]Miranda[/name] - The [name]Tempest[/name]
[name]Maria[/name], [name]Viola[/name] - Twelfth [name]Night[/name] - ([name]Olivia[/name] is in this one, too…)
[name]Hermione[/name], [name]Paulina[/name] - [name]Winter[/name]'s Tale
My favorite [name]Shakespeare[/name] name, and one I think is perfect with [name]Olivia[/name], is [name]Miranda[/name]. It’s well-known but not too popular, and it has the same feminine, fun, sassy, and spunky feel as [name]Olivia[/name]!
I like [name]Matilda[/name] & [name]Harriet[/name]
Other suggestions
[name]Lillian[/name]
[name]Pippa[/name]
[name]Thea[/name]
[name]Jemima[/name]
[name]Katherine[/name]
[name]Lucinda[/name]
[name]Megan[/name]
[name]Freya[/name]
[name]Sadie[/name]
[name]Susanna[/name]
[name]Eleanor[/name]
[name]Isobel[/name]
[name]Amy[/name]
[name]Daniella[/name]
[name]Georgia[/name]
[name]Zara[/name]
[name]Xanthe[/name]
[name]Cora[/name]
[name]Verity[/name]
[name]Briar[/name]
[name]Natasha[/name]
[name]Mischa[/name]
i think you need a girly girl name to keep up with [name]Olivia[/name] maybe
[name]Isabella[/name]
[name]Adabella[/name]
[name]Caitlin[/name]
i like one i read about alice
i think pairing it with any name that is a vowel would be a good idea like…
emma
[name]Emily[/name]
arrianna
[name]Isla[/name] and [name]Matilda[/name] are my favorites from your list… they pair nicely with [name]Olivia[/name]!
I think stick with [name]Isla[/name]! GREAT name and goes wonderfully with [name]Olivia[/name]
[name]Olivia[/name] & [name]Isabelle/name
[name]Olivia[/name] & [name]Beth[/name]
[name]Olivia[/name] & [name]Sarah[/name]
[name]Olivia[/name] & [name]Analise[/name]
[name]Love[/name] [name]Isla[/name]. Sounds great with [name]Olivia[/name].
If stuck, [name]Marissa[/name] is a beautiful and underused name.
[name]Polly[/name], a new fave of mine, would sound great with [name]Olivia[/name]!