I've never liked
Elise. But it flows alright and
Aspen is nice.
A sibling? How about
Sylvie, meaning forest. It's theme-y, but subtle. Others:
Jada,
Garnet,
Liv,
Juno,
Gaia,
Cruz,
Lila,
Zoe,
Thalia, Sonnet,
Lara,
Kaia,
Freya,
Lilith,
Kateri,
Nyree,
Gemma,
Clio,
Leda,
Maia, Trilby,
Sian,
Ione,
Jaya,
Nina,
Jocelyn,
Cara.
Yes, no, maybe so?